Breaking News for sky aficionados

Series of solar flares excites high latitudes, leaves others in the dark

2012-01-31T16:13:00.007+01:00

Several flares and coronal mass ejections between Jan. 19 (see last time graf 2) and 27 caused a lot of excitement and managed to enhance auroral activity at high latitudes but left observers farther away - e.g. in central Europe - waiting in vain. While on Jan. 22 at least the northern British Isles got a nice show, on Jan. 24 - covered in great detail by this live-blog with maaany links - the action remained restricted to around the regular auroral oval. The proton storm the latter CME caused was the strongest since 2003, but the - aurora-relevant - geomagnetic storm never exceeded a meager G1: This made the high-latitude aurora a bit more intense perhaps but it is practically always present, as most news coverage - as confused as ever - failed to point out. Here are links about an X flare on Jan. 27 (video, coverage, more, more and more) and C flares an Jan. 26, all ineffective. Earlier why the M9 flare on Jan. 23 and its CME didn't "work" for lower latitudes, selected high latitude pictures here (from a Hurtigruten ship), here, here, here, here, here, here, here, here and here, videos here, here and here and coverage here, here, here, here, here, here and hier.

Finally the effects of the Jan. 19 flare on Jan. 22 were mostly covered in the live-blog; here are a nice picture, Norwegian videos of Jan. 22 and Jan. 21-23 - and documentation of auroral theft (the original pictured had been linked to twice in the blog) ... More solar-terrestrial links: new efforts in forecasting, an interview on space weather effects, a guide for aurora in Germany, solar wind predictions, the Kp value plotted for Jan. 22-24 (and during a real storm), the lack of solar cycle effects on climate demonstrated during the past minimum, the apparent non-role of the Sun in the Little Ice Age (blame it on volcanos; more and mehr), sunspot physics details, near-Earth electron escape and high solar activity removing space junk from orbit. • Elsewhere in the solar system Uranus has crossed the celestial equator for good and stays north for 42 years now. • Jupiter on Jan. 26 and Jan. 25, Jupiter, Moon & Venus on Jan. 29 (deep; Finland at 62.5°N) and Jan. 27 (video; Slovakia at 48.5°N) and Mars on Jan. 28 (more) and Jan. 17.

Minor planet Eros is in perigee today, the closest in decades! The parallax campaign is in full swing, with the object quick in the sky, also seen in this video and trail image of Jan. 29 - and it's changing its brightness quite a bit as the strange body rotates. • The tiny NEO 2012 BX34 came to within 60,000 km of the Earth's surface: pictures and animations here, here, here and here and stories here, here, here and here. • Plus the physics of lunar impact flashes, an Al Jazeera clip on meteorite searching in Oman - great science on TV at an unexpected place! - and a mini-paper on the Shiva crater candidate.

In the world of comets the weird story of the "shy comet" P/2003 T12 (SOHO) recovered by STEREO now. • Images of comet Garradd of Jan. 31 (just hours ago; more), Jan. 30, Jan. 29 (dito), Jan. 26, Jan. 22 (dito) and Jan. 21. • Comet Lovejoy - here's a great picture collection! - is still there, with an exceedingly faint tail: pictures of Jan. 30 and Jan. 28 - plus a very tough sighting from New Mexico, also mentioned here. • Another article on the comet near the Sun last July.

Sky highlights to be expected in February include the possibility to see all 5 bright planets in one night as Mercury begins its best evening apparition of 2012 in mid-month. There will also be a close Venus-Uranus conjunction on Feb. 9, and a star occultation by Quaoar on Feb. 17. • Finally a story on an amateur SN hunt (20 observers, 200+ successes), another analemma success, observations of a rocket fuel dump and a Yosemite timelapse movie with some astronomy from 2:20-3:20.

Decision on leap second postponed - world time & Earth rotation remain linked (for now)

2012-01-20T22:35:00.007+01:00

A panel of the International Telecommunication Union - which these days feels responsible for defining time, something astronomers used to do - has postponed a decision to abandon the leap second for another three years as no clear majority was evident: see reports here, here, here, here, here, here, here and hier for further details, context and opinons as well as a nice Al Jazeera news clip and reports before the non-decision here, here, here and here. Perhaps the 3 years gained will now be used for an open debate involving society (and astronomers, please!) as a whole? How the differing opinions of the ITU members came to be is hard to fathom; in the U.S. the State Department was in charge, for example, and in Germany the Bundesnetzagentur. Who asked whom for input prior to the 2012 gathering is also difficult to access, e.g. the members of the American Astronomical Society were not asked for their opinion while the IAU somehow felt it had the authority to support abandoning the leap second (according to documents this blog obtained; sorry, no links). Anyway, it didn't happen, and Earth rotation and Universal Time Coordinated remain linked for the time being, with the next leap second due this June 30 anyway.

The biggest news elsewhere in the Universe is a 13 mag. supernova in NGC 3239 in Leo, SN 2012A, which is also discussed here, here, here and here. • The Catalina Real-Time Transient Survey is making headlines with its many discoveries of variable things in the sky; also more insights about and one amateur's light curve of Epsilon Aurigae's last eclipse. • On the Sun an M flare that may have terrestrial FX tomorrow (or perhaps not so much), a Jan. 2 prominence movie and magnetic measurements. • Jupiter on Jan. 15 (more), Jan. 4 (movie!), Jan. 2 (with moons & Moon) and in Nov. 2011 and Mars on Jan. 16, Jan. 15 (more), Jan. 11, Jan. 9, earlier and still earlier, plus a cool 'trailer' for the Transit of Venus.

Comet Lovejoy is still around but the tail of the - formerly 'great' - comet has faded extremely: pictures of Jan. 20, Jan. 19, Jan. 18, Jan. 18+16, Jan. 16, Jan. 15 (with a 43° tail), Jan. 14 (stark processing; at LMC; dito), Jan. 13 (over the LMC), Jan. 12 (dito), Jan. 7, Jan. 6 (dito), Jan. 5 (dito, dito), Jan. 4, Jan. 3 (dito, dito), Jan. 2 (dito, dito), Dec. 31, Dec. 29 and Dec. 28 (the latter two from the ISS), a movie covering 6 days, picture collections here, here, here, here, here, here and here, a visual report from Jan. 2, coverage of Jan. 3 (dito, dito) and early speculations (related video - and a counterview). • Also the July 2011 case of comet observed being destroyed in the sun has been analyzed: press releases here and here, corollary thoughts and coverage here, here and here.

In other comet news comet C/2010 G2 (Hill) is in outburst: pictures of Jan. 12, Jan. 10, Jan. 5, Jan. 3 and Jan. 2, plus the comet in STEREO images and during an earlier outburst. • Comet Garradd on Jan. 16, Jan. 5 and Jan. 4, Arend-Rigaux among galaxies on Jan. 19, comet C/2012 A2 (LINEAR) and many comets with Faulkes. • A reminder about the Eros Parallax Campaign beginning Jan. 28 (more and more) and detections of Eros by yours truly with a simple camera on a tripod with long and even short focal length. • Also a detection of Apophis with a 60 cm scope (not affecting the impact risk - very low anyway - much), an 'Orwellian' retraction of an asteroid and papers on asteroid activity and rotation. • A rare fall of Mars meteorites last year in Marocco is now confirmed (more, more, more, more and more) - and wine aged with a meteorite is making headlines ...

In other news the Quadrantids 2012 didn't perform that well (with a maximum ZHR of only ~80) but were nice for photographers: composite images here, here, here and here, a comparision DSLR vs. video, a video clip and picture collections here, here and here. • How to photograph the ISS crossing the Moon (more) and utter BS about the X-mas Soyuz stage reentry - sigh ... • A call for amateur radio observations (of meteors in Earth's atmosphere) in support of the LADEE mission to the Moon. • And finally another astrophotography contest and a new astrophotography blog - featuring many pictures taken from Bonn, Germany. High contrast & vivid colors despite the urban location of the 50-cm telescope employed!

Lovejoy's tail still dozens of degrees long but surface brightness way down

2012-01-01T15:05:00.003+01:00

Only under the best conditions is the long narrow tail of comet Lovejoy - still stretching for almost 40° - easily visible in the sky, elsewhere it isn't even a naked-eye object anymore: This Great Comet is only a shadow of its former self. Still photographs (exposed for several minutes) continue to show an amazing object, and the fading tail might get even longer by mid-January, though some image enhancement techniques will be necessary to bring its full length out. Some picture collections by Tabur, Garradd, Gerry, Mattiazzo and Hao (more, more, details) from Australia, pictures from Argentina and an undated one.

Selected views of Jan. 1 (more, more and more), Dec. 31 (more and more), Dec. 30 (more, more, more and more in weird projection), Dec. 29 (more), Dec. 28 (more, more, more, more and more), Dec. 27 (more, more, more, more, more, details, more, more, more, more, more, more, a rise video and an ISS view, alt.), Dec. 26 (more and Dec. 21 ... 26), Dec. 25, Dec. 23 and Dec. 22 (in an all-sky video). Also visual reports from Jan. 1 (still 39° tail), Dec. 31 (no longer naked-eye), Dec. 30 (earlier) and Dec. 27 - and coverage of Jan. 1, Dec. 31, Dec. 29, Dec. 28 (dito), Dec. 27 (down; dito, dito) and and Dec. 26. • There are also two new Boattini comets, P/2011 Y2 and C/2011 Y3.

Heavenly highlights in January 2012 - see also hier & hier - include an asteroid transit in front of Betelgeuze (with the star's disk x10 larger than the asteroid; can that be observed?) on Jan. 2, the Quadrantids peaking on Jan. 4 (more & more) and a rare Earth approach of asteroid Eros on Jan. 31: This has led to a call to capture its parallax as a reenactment of a famous technique to measure the AU; concrete details are still being planned. • For the full year 2012 some highlights, what the planets and meteors have in store and what will be occulted by the Moon and minor planets; also a list of planet occultations by the Moon in 2012 and beyond. • Finally a helpful website about the state of space weather, some results from the Eps Aur event - and a FAQ, story (more, more & more), another video, TV coverage and all kinds of stuff (later, still later) about the Dec. 24 Soyuz upper stage reentry over Europe.

Lovejoy survives perigee - and now plays mini-Ikeya-Seki for Oz et al.

2011-12-25T19:18:00.003+01:00

Defying practically all predictions, comet P/2011 W3 (Lovejoy) not only survived perihelion with ease but then formed a long and narrow tail that is well placed for the S. hemisphere now and resembles a small copy of that greatest sungrazer of the 20th century, Ikeya-Seki and giving it a quite good rank among all fine comets. Some picture collections of this amazing comet by V. Tabur, R. McNaught and B. Armstead, protocols of its behavior after and before perihelion, a calculation if its period (roughly 800 years), the lightcurve (that peaked at ~ -4 mag.), various notes in English, French and German, numerous satellite clips around perihelion (also w/an overly dramatic score and as a ballad ...), the geometries for SOHO and STEREO A (more) and various pictures (earlier).

Selected pictures of Dec. 26 local time (dito), Dec. 25 (dito, dito), Dec. 24 (dito, dito, dito, dito, dito, dito, dito, dito, dito, video, another), Dec. 23 (details, more, more, dito, details, more, dito, more, Dec. 22 from the ISS and from the ground (details, more, cloudy, in motion, more), Dec. 21 from the ISS (more & video) and from the ground (dito, dito, dito, dito, dito, details, dito, dito, dito), Dec. 20, Dec. 19 from the ground (earlier) and STEREO A, Dec. 18 from the ground and STEREO A (more), Dec. 17 from the ground (alt., more, explained, dito) and STEREO A (later), Dec. 16/17 LASCO C3 animation, Dec. 14-17 LASCO C3 montage and animation, Dec. 16 LASCO C2 (animation), LASCO C3 and STEREO A, Dec. 15 SDO (alt., alt.) and LASCO C3, Dec. 11 STEREO B and Dec. 4 ground-based.

Visual reports of Dec. 25 (a drawing), Dec. 24 (more), Dec. 23, Dec. 20, Dec. 17 and Dec. 16. Press releases and space agency notes of Dec. 24, Dec. 22, Dec. 16 (more and more), Dec. 15, Dec. 14 and various dates. And news, blog and mailing list coverage of Dec. 25, Dec. 24 (dito), Dec. 23 (dito, dito, dito), Dec. 22 (dito, dito, dito, dito, dito, dito, dito), Dec. 19 (dito), Dec. 18 (dito), Dec. 17 (dito, dito, dito, dito, dito), Dec. 16 (dito, dito, dito, dito, dito, dito, dito, dito, dito), Dec. 15 (dito, dito, dito, dito, more), Dec. 13, Dec. 6 and Dec. 5. • In other small bodies news a big paper on active asteroids (more), a bolide over Canada that may have dropped meteorites (more, more, more, more, more and more), a fine Geminids peak mit a peak ZHR of 200 (picture, another, yet another, composite, more, preview, side effect ...), a preview of the 2012 Quadrantids and a paper on the 2011 Draconids, observed from a plane.

The last total lunar eclipse in 3 years on Dec. 10 was widely observed, with yours truly in an ideal spot in India: this was mentioned in international reports here, here and here. Numerous pictures, reports and websites about this lunar eclipse from around the world can be found e.g. here, here, here, here, here, here, here, here, here, here, here, here, here, here, here, here, here, here, here, here, here, here, here, here, here, here, here, here (the most unusual report - from the Nordkapp!), here, here, here, here, here, here, here, here, here, here, here, here, here, here, here, here, here, here, here, here, here and here (anyone volunteering to sort them by country or longitude? :-) - also a preview of what the LRO planned and a bizarre headline ...

In other news insights into the chemistry of Pluto, an apparent detection of the rings of Uranus by an amateur (more), recent hi-res Jupiters, all planets in the sky now (here they are), Moon, Venus & Mercury on Nov. 27, space weather visuals, insights, lunar effects and prediction attempts - and a hectic aurora movie. • Insights into the progenitor of SN 2011fe (more, more, more, more, more, more and more press releases and coverage here and hier). • Finally the reentry of a Soyuz upper stage was widely observed in Central Europe yesterday (official word, more and more analysis, further stories here and here and more witness reports) - and an article (p.10-11) on imaging satellites.

First ground-based discovery of a Kreutz comet since 1970 - by an Aussie amateur!

2011-12-03T23:22:00.008+01:00

Many hundreds of sun-grazing comets of the Kreutz family have been found in recent decades by Sun-watching satellites with their coronagraph cameras when they were already very close to the Sun - but with C/2011 W3 (Lovejoy) it was different! For the first time since 1970 this Kreutz comet was discovered weeks before perihelion: by Australian amateur Terry Lovejoy who incidentally also was a pioneer in sungrazer detection in SOHO images. Already before it had a proper number, the object's orbit hinted at a sungrazer, and the 1st 'official' orbit has Lovejoy reach perihelion exactly on Dec. 16 at 0:00 UTC at a solar center distance of 0.00589 AU - that means a mere 140,000 km above the solar photosphere. While ground-discovered Kreutz comets have often become great sky shows, it's doubtful that C/2011 W3 - still very faint: pictures here and here (scroll down) - will survive its brush with the Sun and follow the tradition. Then again one never knows - and there should at least be a fine performance when Lovejoy enters the FOV of SOHO's coronagraphs on Dec. 12.

In other comet news there was yet another amateur discovery - and the first from African soil in some time: comet P/2011 W2 (Rinner), now celebrated in France and elsewhere but always staying faint like now. • Comet Garradd remains a dud for visual observers and a beauty for photographers as pictures from Nov. 28 (more!), Nov. 27, Nov. 25. (looks like Halley in April 1986, no?), Nov. 22, Nov. 20, Nov. 19 (more), Nov. 15 and Oct. 28 show; also comets Hill and P/2011 UH55. • The Leonids of 2011 reached only a ZHR of 20, as expected, but produced nice fireballs as seen e.g. here, here and here; also a long report about the Draconids 2011 over Egypt. • And talking about things hitting the Earth - or not - news from 65 Myr ago, 200 Myr ago and 252 Myr ago (more and mehr).

Yet more results re. NEO 2005 YU55 keep trickling in: joint lightcurves (scroll down), a parallax demonstration, the results from Herschel [Deutsch] (some numbers), the Arecibo radar 'images' and processed - kind of - Goldstone data (plus a summary of earlier stuff). • Also a successful observation of an occultation by Kalliope and all chords, a paper on Themis et al. and a press release on a student NEO discovery. • Some fine Jupiter images of Nov. 25, Nov. 21 (amazing; more), Nov. 16, Nov. 12 and Oct. 21, a weird animation from here. • Plus some constellations: Moon & Venus on Nov. 27 and Nov. 26 (also an attempt from Austria), Moon & Saturn on Nov. 23 and Venus & Mercury on Nov. 13.

There was a partial solar eclipse on Nov. 25 which could be observed only in the deepest South: some pictures & stories from South Africa (more) and Antarctica (more), collections here, here, here and here, the funny view from Hinode which saw three eclipses, coverage here, here (more) and here and previews here, here, here and here. • Also a podcast & transcript on upcoming solar eclipse science and stories on the future of the solar cycle, the shape of the solar wind [Deutsch], new Cluster observations (more), solar monitoring by the Proba 2 spacecraft and progress in solar storm forecasting.

In other news SN 2011dh in M 51 is still producing science headlines, like on the pre-explosion variability of the progenitor and early radio interferometry observations of the remnant; the latter paper and many more on 2011dh had already been discussed here (and the former one is here). • An amateur apparently captured the dust disk of Beta Pic with just a 10". • A nice 13-min. movie on Namibia's skies, artistic photographs of star trails and experiences on a ship hunting the Aurora off Norway. • The reentry of the latest Soyuz filmed from the ISS (1st minute), Chinese amateurs watching Tiangong, David Levy's logs online, TGFs and the future of UTC after the likely end of the leap second. • Among the sky events in December the lunar eclipse on the 10th dominates: more previews here, here, here, here and here, with a call for observations.

Earth visit of big, dark asteroid widely observed with all means

2011-11-13T15:00:00.007+01:00

Only a fraction of the scientific data recorded with everything from big radar dishes to a 10-meter telescope with adaptive optics to the large IR satellite Herschel have been reported yet, but it can already be stated 2005 YU55 will probably be the best studied minor planet (not directly visited by a spacecraft) ever: a live-blog tracked the news from Nov. 6 til 10 and has many pictures, videos and links; since wrapping I've seen more videos here, here, here, here and here - also an improved radar movie, a late wire story and a simulation of what would have happened had YU55 impacted Earth.

In other planetary system news a long press release on a meteorite found by a Missouri farmer - a 17-kilogram pallasite! - and pictures of a bright Dutch bolide of Nov. 12. • Another - very faint - detection of (ex-)Elenin on Nov. 8, a great picture of comet Garradd of Oct. 30 - and C/2010 S1 (LINEAR) approaching the Bubble Nebula on Nov. 12. • How Venus & Mercury were easy - when you were in Australia. • Some selected Jupiter images of Nov. 13, Nov. 6 (more) and Oct. 23 - and a breathtaking animation of Jupiter images taken with the Pic du Midi 1 m telescope in October!

The huge sunspot group 1339 is almost history after - despite breathless articles like here, here and here - crossing the solar disk w/o further incidents: some selected pictures of a fine prominence today, the white and H-Alpha Sun (more) and a huge filament on Nov. 12, the white Sun full of spots on Nov. 11, a spotted sunrise on Nov. 10, the full disk + detail on Nov. 9, the group at the center on Nov. 8, the group and a spotty sunset (another one = an APOD) on Nov. 7, the full disk, detail, H-Alpha and spotty sunset on Nov. 6, detailled drawings of Nov. 5 (also a photo) of Nov.5 and earlier drawings of AR 1339. • Plus no superflares (more), strange jumping sundogs - and the likely end of the leap second.

Biggest sunspot group in years crossing the disk; already one X flare seen

2011-11-06T17:50:00.003+01:00

The new activity region 1339 - a full-disk view of today and another close-up - is now crackling with M-class flares as it approaches the center of the disk. Just after arriving around the limb it had fired off an X-class flare ("Ein Flare der ...") on Nov. 3 that made some headlines but not another one - thus geophysical effects of AR 1339 have so far been absent. • Also some truly great aurora images (in the picture stream, both directions), the anatomy of a geomagnetic storm, a detailled report and 3 videos from the German outburst of Oct. 24/25 (also a Canadian view) and a solar cycle primer. Plus a paper on the solar corona and how and why visual and photographic impressions differ so much.

Elsewhere in the Galaxy the Epsilon Aurigae eclipse is not completely over, with lingering spectroscopic effects; also the 9th campaign newsletter. And some recent images of M 101 and its fading supernovae; some science results (also about the one in M 51) can be found linked here. • Back in the solar system Venus & Mercury on Nov. 5th and Oct. 27, Jupiter's Io covering its shadow and unusual events around opposition (more, more and more). • An amateur non-detection (but great 2006 pics!) of the bright Uranus spot (more and more). • The full paper on Eris' diameter, a press release and yet more stories here, here and here.

The most unusual event of the month - with few other highlights - is the close approach of the 400-meter asteroid 2005 YU55 which already being tracked with radar by Goldstone, supporting planned Herschel observations: more previews of the hard-to-observe event here, here, here, here (earlier), here, here, here, here, here, here, here, here and here. Also recordings of two related chats here and here and articles in German hier, hier and here, plus more media reax. • Also La Palma crossing M 31 again, the stones from 2008 TC3 and a CBET on the Draconids, a rare visual observation and images of Nov. 1 (animated) and Oct. 27 (processed and explained), a looong rant about and Indonesian coverage of ex-Elenin - and Garradd on Oct. 30.

Bright spot emerges on Uranus - can amateurs track it (and thus help Hubble)?

2011-10-27T15:29:00.010+02:00

Observations with one of the Gemini 8-m telescopes show a very bright spot that has suddenly appeared on Uranus and is at least 3 times brighter than the remote planet's disk: "If this is a convectively driven white feature it may evolve to larger size and brighter appearance on the next few days," says an unusual alert message distributed via The Astronomer network earlier today. Moreover amateur images of Uranus are now considered "essential to study this feature and its precise drift rate to assist possible observation with other highly-priority telescopes such as the HST." Uranus subtends 3.7" in the sky, and the bright cloud feature is at least 0.33 arc seconds making this feature potentially accessible to relatively modest telescopes. On 2011 October 26 at 08:06 UTC when the linked picture was taken the spot was at 323° west longitude and 22.5° north; the current estimate for the rotation period of this feature is 17.24 hours. • A slightly easier target is Jupiter, now in opposition: selected images from Oct. 24 (46 cm scope), Oct. 22 (20 cm - animation), Oct. 13 (1 meter), Oct. 3 (25 cm) and Sep. 26 (23 cm).

Comet Elenin has been recovered after all, now that the Moon is out of the way, but only as an extremely diffuse dust cloud with not one individual fragment brighter than 22.5 mag.: reports on the hunt and what one can see (or rather image) from Oct. 25, Oct 24 (more), Oct. 23 (more), Oct. 21 and Oct. 15, pictures of Oct. 24, Oct. 23 (more, more and with just 8 cm aperture), Oct. 22 (more), Oct. 21 (negative), Oct. 15 (positive after looking hard) and Oct. 14 (negative), another claimed visual observation (why such a small 'coma' size?), a long essay on visual comet observing - and a very stupid NASA press release asking for Elenin to "be forgotten". Rather forget such dumb advice and observe the most unusual ... thing that Elenin has turned into while it's still possible (it's now receding from both Sun and Earth).

In other comet news the first Jupiter Trojan comet has been found - and Bressi may be interesting. • Pictures of Honda-Mrkos-Pajdusakova from Oct. 15, Oct. 7 and Sep. 30 (with a mountain) and Garradd - which now has a nice plasma tail as well! - of Oct. 23 (more), Oct. 17 (more), Oct. 15 (more) and Oct. 14 (more). • Another - smaller - comet hit the Sun on Oct. 19 (earlier, still earlier), a video on the Oct. 1 case and 5 years of comets observed by the STEREO mission. • The physics of impacts on Earth, an observing guide for and JPL Release about coming NEO 2005 YU55, an asteroid crossing M 31 (movie) - where it was mistaken for a nova! - and a Subaru Release about Scheila's outburst.

In other solar system news Venus and Mercury low in the evening sky on Oct. 24 (USA) and Oct. 22 (Australia and - w/o Mercury - Austria) - the new evening apparition of Venus will end with the solar transit next June! • The equal diameters of Eris & Pluto also discussed here, here, here, here, hier, hier, hier and earlier here. • The Orionids delivered a nice show, only a maximum ZHR of 50, but it looked great for some (another and another night); also an all-sky sum image, a spectrum (more) and a picture. • From the Draconids a detailled story with pictures from the NE German campaign, another video from the NL, observations by ESA, a German video (AVIS2), the radiant from 6 video cameras and a Spanish composite image and report. • Also a night with 5 showers, no evidence for interstellar meteoroids and a German fireball. • This month's full moon was the smallest of the year: a comparision with the biggest one (alt.) and a list of big ones.

In other news there was an aurora outburst Oct. 24/25 over e.g. Germany and the U.S.: a great German timelapse video, a fine gallery, pictures from all over Germany, Alabama (w/video) and N. Germany and coverage here, here, here, here and here. The CME that caused it was launched on Oct. 22 as was another one that headed towards Mars; there was a lot to see on the Sun that day. • Weird NLC-like looking clouds may have been caused by the 1st S. American Soyuz launch, and a picture of Spektr R deep in space. • A German press release on that rare triple rainbow (with the full paper) - and a double rainbow with a stupid caption (as if it stretches from one place to another). • And then there was a bizarre paper on things in front of the Sun in 1883 which some rightly attacked (mehr) but others found at least intriguing. And as if ordered: a mystery crossing the solar disk just this month ...

Comet Elenin gone for good (though some still claim detections, even sightings)

2011-10-12T23:17:00.004+02:00

With this negative report, setting tough upper limits on the brightness of whatever may be left of much-expected/hyped/feared comet C/2009 X1 (Elenin) on Oct. 9 and 10 the hunt seemed to be over - yet there are claims that the STEREO satellites can still see it (they probably did in the 2nd half of September; see also this and this tweet) and even of a visual sighting right when the big scopes saw exactly nothing. How could that be? A major mystery right now that puzzles even leading comet gurus ... anyway, this alleged detection of Elenin by Elenin himself (also reported e.g. here [earlier] and here) was probably just noise. Now the Moon is spoiling the view in the morning where the comet - or rather its theoretical positing - is quickly climbing higher; by about Oct. 23 deep observations will again be possible and should settle the issue for good.

In other comet news the plasma tail of comet H-M-P continued to amaze: big picture collection and shots of Oct. 11, Oct. 6 (wider), Oct. 5, Oct. 4, Oct. 3 (b/w), Oct. 2 and Oct. 1. • Comet Garradd on Oct. 10, Oct. 3 and Sep. 29 and the comets C/2011 P1 (McNaught) and C/2011 S2 (Kowalski). • The fate of the Great Kreutz Comet of 2011 - and some funny sungrazer/CME statistics (not proving much yet). • The outburst of Scheila modelled - and modelled again. • The Draconids outburst was covered by a huge live-blog with numerous links; a nice persistent train and meteor. • A meteorite hit a house near Paris in the summer (more, more, mehr), and the complex origin of 2008 TC3 and its meteorites.

In other small bodies news a NEO discovery by amateurs 'working for' ESA's Awareness, a call for observations for an upcoming NEO passage, observations of a past one - and more astrometry of Apophis (strangely missing from the JPL analysis of impact risk). • The moons of Minerva (more and more) and an extremely tilted KBO contact binary (more). • The star occultation's outcome was that the diameter of Eris is just like Pluto's (also covered here and here - after some some embargo problems that suddenly evaporated) - and the temperatures on Makemake.

In other news Jupiter on Aug. 18 til Oct. 4, Oct. 3, Oct. 2/3 (map) and Oct. 2 (more). • Solar eclipses causing wakes in the atmosphere. • The AAVSO is 100 (from there a 100a of SS Cyg video from this source) and private lightcurves of the SN in M 101. • A quadruple rainbow makes headlines here, here, here, here and here. • A story about Damian Peach, the solar system photographer. • Observing NanoSail D in hi-res. • A summary brochure of the Decadal Survey. • The world's largest clock dial in Mekka. • And the smallest full moon was obviously smaller than others (more and more) - don't let them tell you that the effect isn't clear to the naked eye!

Best aurora of the cycle yet caused by impressive sunspot group

2011-10-02T13:53:00.000+02:00

Solar activity is now clearly on the rise, as are space weather effects right here on Earth - and the Activity Regipn 1302 which crossed the disk in recent days (more pictures here, here and here) drove the message home: mainly with a major flare on Sep. 24 that caused a strong geomagnetic storm on Sep. 26 (also discussed here, here, here, here, here and elsewhere). And this, in turn, led to the best aurora of the current cycle, beating the brief August show: some summaries are here (incl. a crappy picture by yours truly; the aurora is the reddish glow on the right), here (more), hier (table) and hier. Further pictures, videos and reports from NRW in Germany (best pix from Bonn) and elsewhere in Germany (more, more, more and more), Austria, Norway (more, more and more), the Netherlands (more), Slovenia, Sweden, Finland, the Outer Hebrides, the U.K. (more, more) and the U.S. (more). There had been another flare on Sep. 22 (more, more and a CME series Sep. 18/9; also the 'secret lives' of flares and a timelapse aurora video from Finland.

Elsewhere in the solar system IR Keck images of Neptune and Uranus (more and more), amateur images of Jupiter of Oct. 1, Sep. 26 (also w/8" - and structure on Ganymede!) and Sep. 22, and Mars on Sep. 26. • NEOWISE has revised the statistics of NEOs (alt., ident.; coverage here, here, here, here and hier) and the history of the Chicxulub impactor (covered here, here, here, here, hier and hier); the latter's role in the dino death is still under debate, by the way. • Among comets there were a bright Kreutz, lots of structure in 45P/H-M-P's tail & Jupiter near-crash (H-M-P today), new main belt comet P/2010 R2 (La Sagra), further fragmentation in 213P/van Ness (more, more), new comet Gibbs, no LASCO sighting of damaged Elenin and a naked-eye sighting of Garradd (which did not fade afterwards); also picture of Sep.30, Sep. 26(!), Sep. 24 and Sep. 21.

Sky highlights in October - see overview articles here, hier and here - include:

Oct. 1-2: Mars passes Praesepe, the star cluster.
Oct. 8 (around 20:00 UTC): Possible outburst of the Draconids (more, more), but the predictions remain confusing - and the event coincides with Observe the Moon Night which is not a good night for meteor watching ...
Oct. 21-22: Peak of the Orionids; less lunar interference than with the Draconids, so worth a look.
Oct. 27/8: Conjunction of Moon, Venus and Mercury low in the evening, invisible in higher N latitudes.
Oct. 29: Jupiter in opposition with -2.9 mag.; it's awfully bright already now (closest to Earth on Oct. 27 already).

Meanwhile the supernova in M 101 has faded a full magnitude from the peak, to 10.9 mag. - and the hunt is on for Snoopy from the unsung Apollo 10 mission ...

After Elenin's rapid decay: will anything be seen again

2011-09-16T14:26:00.003+02:00

when the comet or rather its debris cloud - now impossible to observe from the ground - will make an appearance in the field of view of SOHO's coronagraph LASCO 3 a week from now? Despite a brightness enhancement of its dust due to forward scattering - the comet is practically between us and the Sun - the SOHO comet experts are pessimistic, given the apparently complete decay of Elenin beginning August 20. The most diligent observer of its fate was an Australian: His pictures document the dramatic change of the comet's appearance as well as its sudden break in the light curve - by September 14 it had fallen below 10th magnitude again. The comet had also been followed by the STEREO spacecraft (images of Sep. 10 [enhanced], Aug. 25, Aug. 23 and Aug. 21), another Australian and radio astronomers; stories about the decay also here, here (earlier), here, here (earlier), hier, hier and hier.

In other comet news van Ness may also have fragmented again (more, more). • Garrad continues to be tracked widely as the comet passes numerous deep sky objects: many pictures, esp. from the 'coathanger' visit and selected images of Sep. 10 (more), Sep. 7, Sep. 6, Sep. 3 (more, more, more and more), Sep. 2 (more, more and more), Aug. 29, Aug. 28, Aug. 27 (more and more), Aug. 26 (more, more, more, more, more, more, more and more) and Aug. 25. • Also new comets from Russia (media report), PanSTARRS and SWAN.

In further small bodies news thoughts on color diversity in the Kuiper Belt and tectonics on and oceans in icy worlds. • Hailing the outcome of the Antiope occultation. • Everyone wants a satellite to hunt for NEOs. • A major bolide over the SW U.S. on Sep. 14: video & analysis, NASA statement (alt.) and early stories here, here, here, here and here; also an earlier bolide over Atlanta (more) - and details about the meteorite rain in Kenya.

On the Sun a series of flares kept observers on edge: there were X flares on Sep. 7 (video, pictures, story, follow-up, aurorae, pictures) and Sep. 6 (video, story, more and an M flare on Sep. 5. Also insights into late flare phases (more, more, more, more and mehr), fast substorms, linked solar eruptions, climate (non-)effectsand old Mariner solar wind data (and the usual fear-mongering about the Sun). • The 2017 solar eclipse 'megamovie' ideas gets also advertised here, here and here. • There is now a Zeta Aur campaign (not for visual observers) and a Nova Sco 2011 #2 - while the developments with SN 2011fe in M101 - just past a peak at 9.9 mag. vis. - are covered here and here with numerous links.

In other news there was once more major confusion about Ramadan's end as observers struggled with the lunar crescent. • Another ridiculous contrail mistaken for a bolide, also discussed here, here and hier. • A huge flare from a satellite and hi-res images of NanoSail D from August and earlier. • The winners of Astronomy Photographer 2011 get covered e.g. here, here and here. • And finally the sky highlights for September - besides Garradd and the supernova - consist mainly of the opposition of Uranus on Sep. 25 when the planet reaches 5.7 mag. Dwarf planet (1) Ceres is in opposition today, but has only 7.7 mag.

Closest Type Ia supernova in decades explodes in galaxy Messier 101, brightening rapidly, should reach 10-11 mag. soon

2011-08-26T03:43:00.002+02:00

It was discovered very early in its lightcurve, and - as hectic reports indicate - brightened by several magnitudes over just the first day, reaching some 13 mag. right now: early pictures of the galaxy with the SN - no proper number yet - can be seen here, here and here while the situation regarding a progenitor isn't quite clear yet. What is clear is that a Ia supernova that close is a great opportunity for science as also reflected in quick press releases from LBL and UCSB; more early stories here, here and here. If a typical case, the brightness of the SN in M 101 should climb to 11 or even 10 mag. in the coming days, easily surpassing the SN in M 51 some weeks ago.

On the Sun the evolution of a spot group and a weird prominence on Aug. 19. • CMEs can now be tracked all the way to Earth by STEREO: press material here, here, here, here, here and here. • Speculation about solar storms in future decades (complex relationships). • A method to detect sunspots before they're seen: press material here, here and here = here and stories here, here, here, hier, hier, hier and hier plus in a video. • A proposal for a 2017 eclipse megamovie, also hailed here, the TSI of the past and an Aug. 23 aurora.

Regarding comets some solar forward scatter math for Elenin which may be decaying though; also STEREO pictures of Aug. 19, Aug. 16 and Aug. 15 and another anti-hoax video. • Garradd on Aug. 22, Aug. 21 (more and more), Aug. 20 (more, more and more), Aug. 18 and Aug. 16. • Van Ness on Aug. 22 (fragment B still there) and a new comet PANSTARRS. • There could/should be meteors after an August 8 event in the U.S. (more), and from a Kenyan fall widely reported in July impressive specimen are in.

In other news from the Perseids - the peak stayed at a meager 63 - a report from the Provence and video stills plus a video with analysis of the ISS case. • A report on the Target NEO study and stats from the La Sagra NEO Hunt. • A Caltech Release, the final part of the story and another one on strange KBO 2007 OR10. • More sober and combative thoughs by plus an interview with Mike Brown on dwarf planets, a press release on wide KBO binaris and what happened 5 years ago. • The best image yet (I know) of NanoSail D and its blinking pattern, plus a fine image of doomed ROSAT. • Finally a nice timelapse movie and another one.

Full moon-lit Perseids weak even after correcting: ZHRmax ~ 70

2011-08-17T19:22:00.002+02:00

Initial poor Impressions of the strength of the 2011 Perseids, heavily bathed in moonshine, have since been confirmed: The zenithal hourly rate reached only about 70 just before noon UTC on Aug. 13 (and this includes corrections for the depressed limiting magnitude). Still - as every year - photographers could get happy with the show: a collage of many perseid streaks and individual ones here, here, here, here and here. Not many are seen in this video, while another one contains many insects ... The most talked-about Perseid image was one taken from the ISS, of course: My research into earlier similar successes is also acknowledged here while different versions of the image are seen here, here and here. • In other meteor news a Dutch expedition to Namibia yielded 2000 meteors, detailled papers and more about the upcoming Draconids is linked here, and there's a strange report from Japan ...

In other small bodies news comet Garradd on Aug. 15, Aug. 14, Aug. 10, Aug. 9 (also an animation), Aug. 7 (more) and Aug. 6. • 45P/H-M-P close to Earth was covered here, here and hier. • Split comet 214P/van Ness on Aug. 9 and Aug. 7 (more) - the 2nd nucleus was seen as early as July 12, by the way. • Comet Elenin on Aug. 13 and in the FOV of a STEREO satellite (movie included!); also an observing guide and a NASA FAQ about Elenin BS which later spawned a JPL Press Release and stories here and here. • And another McNaught discovery ... • A long list of dwarf planet candidates, the case of Kuiper belt object 2007 OR10 (also as a story here and here, KBO hunting for New Horizons and a prediction of a Pluto ring.

Elsewhere in the Universe a small but cute Jupiter of Aug. 12. • A lot of solar activity: a new AR - 1271 - has appeared at the limb, prominence movies of Aug. 16 and Aug. 10 and the biggest solar flare of the cycle on Aug. 9, causing lots of coverage but few effects as it happened at the limb. Future ones may be more effective: solar flare primers as a video and a story. Plus a paper on new scientific insights from solar eclipse observations in the past 5 years. • A possible Nova in Lupus has been confirmed, the progenitor of the SN in M 51 (the claims here are questioned, BTW), and a call for continued monitoring of Eps Aur. • The Aug. 6 aurora from Scotland, Germany (a review) and Canada (a twilight video). • NLCs in the U.K. on Aug. 3 and Finland on July 21. • Some candidates for astrophotographer of the year, some pretty space pics (big!) and NanoSail D flashing over Europe.

Solar action week culminates in aurorae over Europe and North America

2011-08-06T21:14:00.006+02:00

First three major sunspot groups were crossing the disk simultaneously, then a barrage of coronal mass ejections moved towards Earth in a complex pattern, and finally a nice auroral storm occured last night with a show - where clear ... - from Germany to the U.K. to the U.S. and Canada: solar activity is on the rise, the drought is over! From the aurora show reports and pictures from Germany (where Kiel had the best view), the U.K. (same; more and more; same), from Minnesota in the U.S. and Canada (also a timelapse video). The solar flares and CMEs responsible were amply discussed before, like here, here, here, here, here, here and here. And the sunspots themselves were observed widely, e.g. on August 2 at sunset (same; more) or on Aug. 1, July 31 and July 30 (public event).

In the world of comets Garradd (more, more, more and mehr general reports) was widely observed passing near globular cluster Messier 15 on August 1 and 2: images of Aug. 4, Aug. 3 and 2 (more, more, more, more, more, more, more, more, more, more, more, more, more, more, more and more), Aug. 1 (more and more) July 31 (high contrast; more, more and more), July 30 (more) and July 29. • Comet 213P/van Ness has split and also displays a nice antitail: a report (earlier), more observations here and here, here, more pictures and an MPEC. • The STEREO B spacecraft has observed comet Elenin from close: more, more, more and an animation, plus an Aug. 2 ground-based image. • A 5 arc min conjunction of 2 comets, both extremely faint.

Elsewhere in the Universe Several new Kuiper Belt Objects were found in the Southern skies, including 3 potential dwarf planets, another KBO has a weird spectrum, and there is now considerable effort to find suitable KBOs for New Horizons to visit after Pluto. • A great animation shows how chaotic the orbit of Earth Trojan 2010 TK7 is; the small asteroid is also observed by amateurs (more, more) - and the Faulkes scopes are useful anyway for discoveries. • Pictures of Jupiter on August 5, the day Juno was launched to the planet, and July 31. • The young Moon on Aug. 1 in the U.S. and - with Mercury - Australia. • Currently there are two novae of 17 mag. in Messier 31. • NLCs on Aug. 2 in Germany and Aug. 1 in Norway and Germany. • And an observation of NanoSail D on July 31 in Finland.

What the comets Elenin, Garradd and PANSTARRS will (perhaps) look like in your sky

2011-07-31T02:41:00.010+02:00

Three comets are approaching right now that could be good or even really good: Elenin in 2011, Garradd in 2012 and PANSTARRS in 2013. Here are general visibility conditions calculated for Bonn (51°N), La Palma (28°N) and Jo'burg (26°S), with the brightness based on current visual observations (available only for Elenin and Garradd) and further behavior as assumed by the JPL's HORIZONS on-line solar system data and ephemeris computation service which is also used for the topocentric situation. In a nutshell: Elenin this October will never be easy and/or impressive but fine for specialists, Garradd coming February will be very easy but only at +6 mag. - and PANSTARRS (the orbit is still improving every few days) should cross the zero magnitude boundary but will be close to the horizon whereever you are.

C/2010 X1 (Elenin) - Bonn:
- Early til mid-September: extremely low at dusk at 5 to 4 mag., then lost
- Ca. October 3: rapid reappearance at dawn at 4.5 mag., better each day
- October 6: Already 10° high when astronomical twilight begins; still 4.5 mag., no Moon
- October 9 (best view): At 20° when twilight begins; 4.5-5.0 mag., Moon just set
- October 10-15: at 30-45° when twilight starts, 5.0 mag., bright Moon interferes!
- October 21: already at 30° when waning crescent rises, 5.5 mag.
- October 25-30 (pretty good): transits at 69° just before twilight begins, Moon gone, 6.0-6.5 mag.
Elenin - La Palma:
- Early September: about 5° high in nautical evening twilight at 5 to 4 mag., window disappearing by mid-month
- Ca. October 3: rapid reappearance at dawn at 4.5 mag., better each day
- October 5: at 10° when astronomical twilight begins, 4.5 mag.; no Moon
- October 10 (best view): at 25° when twilight stars, 5.0 mag. just no Moon which interferes later
- October 25 (pretty good): comet near zenith, no Moon, 6.0 mag.
Elenin - Jo'burg:
- September 3-13: up to 20° in nautical evening twilight at 5 to 4 mag., but with brightening Moon always present
- October 10: morning reappearance at 10° with 5.0 mag.
- October 25-30: transits without Moon at 30° with 6.0-6.5 mag.
C/2009 P1 (Garradd) - Bonn (situation similar but altitude lower when farther to the South):
- January 19-29, 2012: rising from 0° to 50° in the 2nd half of the night, 6.5 mag., no Moon
- February 15-25: rising from 15° to 70° through the night, 6.0 mag., no Moon
- March 14-28: setting from 70° to 40° through the night, 6.5-7.0 mag., no Moon
C/2011 L4 (PANSTARRS) - Bonn:
- March 10, 2013: at 3° in bright evening twilight, but with -0.6 mag. = maximum brightness
- March 13: at 6° in bright twilight, with -0.3 mag.
- March 16: at 6° in deep evening twilight, with +0.3 mag.
- late March: at 10° without twilight, with 2 to 3 mag. but bright Moon interference
- March 31: at 10° in dark sky, with 3.5 mag., Moon just gone
PANSTARRS - La Palma:
- March 6, 2013: 3° in bright dusk, but at -0.3 mag.
- March 8: 3° in bright dusk, at -0.5 mag.
- March 10: 5° in bright dusk, at -0.6 mag. = maximum brightness
- March 15: 6° in dusk, at 0 mag.
- March 20: 7° in dusk, at +1.5 mag.
PANSTARRS - Jo'burg:
- March 15, 2013: deep in evening twilight with 0 mag., little improvement til end of March

Speaking of comets, there is another Elenin now (more), pictures of 45P/Honda-Mrkos-Pajdusakova of July 27 (more) and July 26, a visual report and pictures of Garradd of July 30, July 29 (more, more and more), July 28, July 26 and July 25 (more), SOHO observations of fading Hartley 2 - and a paper and CBET on a new meteor shower that may indicate an unknown comet threat. • Stories about a meteorite fall in Kenya, a fireball in Texas and a big meteorite (more, more) in China.

Turning to asteroids the campaign to observe a star occultation by double asteroid (90) Antiope in the US was a major success, as these chords demonstrate; more reports here and here, plus a lightcurve. • The first Trojan of the Earth has been found: a paper, animations, an extrapolation, press releases here, here, here and here and stories here, here, here, here, here, here, here, here, here, here, here, here, here, hier, hier and hier. An alleged Uranus Trojan (which would also be a first) is pretty dubious, though (more).

• A fourth satellite of Pluto has been found in HST images - and its correct name is S/2011 (134340) 1 and not "P4": a CBET, press releases here, here and here and stories here, here, here, here, here, here, here, here, here, here, here, here, here and hier. (Before someone asks: Having one or more satellites has nothing whatsoever to do with an object being a planet, dwarf planet or minor planet - just look at the long table of minor planet moons already found!) Also more on the star occultation by Pluto and Haumea's ice. The Moon & Mars from Oz on July 28. And the successful demonstration of the elliptical orbit of the Moon!

In other news on the Sun there are 3 nice groups right now (with an M9 flare on July 30), and there was a cool eruption, while science-wise TSI measurements are problematic, the GIOVE satellites watch for radiation and Alfvén waves are again blamed for coronal heating effects: press releases here and here and stories here, here, here, hier, hier, hier und hier. Plus aurora observations during STS-135. • Amateurs found yet another planetary nebula (more, more - and a weird story ...). • More NLCs from Germany on July 26, the UK on July 23, the UK and Finland on July 22 and the UK on July 18.

• The fiery return of STS-135, Atlantis' final Sun transit (more), many ISS pics in front of the Sun, the ISS in daylight, the ISS & Atlantis over Oz (more, more) and the docked pair crossing the Sun. • Highlights of August 2011 include a - not that - close approach by (3103) Eger on Aug. 4, the Opposition of (4) Vesta on Aug. 5 (with Ceres in the vicinity, too), the Moon-swamped Perseids on Aug. 13, a close approach of comet 45P on Aug. 15, Neptune's opposition on Aug. 23 and the conjunction of (15) Eunomia and 42 Per on Aug. 25.

Pretty good star occultation by asteroid for the U.S. - and to be webcast!

2011-07-16T23:38:00.005+02:00

A rare eclipse of a star visible - in principle - in binoculars by a double asteroid, (90) Antiope, will be visible in Western parts of the U.S. and central Canada in the night 18/19 July: The eclipse of the star LQ Aquarii will last up to 30 seconds in a 125-mile-wide path from the San Francisco Bay area to Boise and W. Montana, then crossing the border (and into bright dawn), and a few who happen to be in the right place might see two eclipses, one by each component of the Antiope pair. Anyone in the path can help accurately measure the size and shape of the objects by making simple observations of the eclipse , though, and the International Occultation Timing Association (IOTA) seeks as many observations of the eclipse as possible. The Moon will be nearby and bright, making the 6.7-mag. star hard to see with small optics - but if you aren't there, don't have clear skies or suitable optics, don't worry: The event will be webcast plus recorded with a lot of cameras!

In other solar system stories meteorites & the law, the NEO 2002 NY40 - many saw rushing thru the sky - as a bolide source, and bolide stories from New Zealand and Brazil. • While comet Garradd is not in outburst, it's still worth observing, as pictures of July 10, July 9, July 8 and July 7 - by M. Jäger - show. • News comets C/2011 N1 and N2, the big sungrazer was also seen in front of the Sun (enhanced), but why is unclear - and Hartley 2 had a dust trail! • The June lunar eclipse in a wide-angle time-lapse movie from Tajikistan and pictures from Namibia, Israel and Italy; also the umbra study gets mentioned. • One fish-eye picture with a lot of planets on July 9 - and Jupiter close-ups of July 16 (another one) and July 11.

From the Sun thoughts about flares on 7 June 2011 and 14 July 2000 (still a science topic!), also new ways to measure magnetism around the Sun. • The light curve of SN 2011 dh in M 51 so far (and pictures of July 12 and July 9), the unusual brightness of Del Sco and the light curve of Eps Aur. • More nice NLC displays over the U.K. on July 14, Germany and the U.K. (more, more, more, more, more, more, more and more) and elsewhere on July 10, from the U.K. on July 7/8 (and stream: more, more and more), from Sweden on July 5 and Ireland on July 2. • A meteor camera recorded sprites. • And for the last time the ISS w/shuttle in front of the Sun (more), also a windy video and report about another transit, a glory seen from a camera on the launching shuttle - and a report on amateur astronomers imaging the launch.

Huge noctilucent cloud displays seen at appropriate northern latitudes

2011-07-06T21:27:00.004+02:00

Early July marks the middle of the 'official' northern NLC season from mid-May to mid-August - and this year these weird clouds at 80 to 85 km delivered, although mainly for latitudes around 55°N, with the most spectacular reports and pictures coming from Cumbria (northern England) and Scotland, esp. on the morning of July 3. A so-so display over Germany in the night July 5/6 (also sightings in the U.S.). The great U.K. outburst on the morning of July 3 reported in all detail from Cumbria and also by another Cumbrian (picture stream, also here and here, with more here, here, here, here and here; got even in one paper) and a Scot (another, another and another) and another and another Brit, plus more, more and more pictures. From July 2 a cellphone and more U.S. images, a moderate U.K. morning show (more, more, another observer, more) and German sightings. From July 1 another U.K. report and Scottish pictures plus German sightings, also on June 29. Plus a Dutch report and a growing gallery.

Solar system small bodies: an updated lightcurve and animation of it, another big page and trailed images of NEA 2011 MD - which came so close that Earth's oblateness had orbital effects! • A recording of a webcast of a star occultation by an asteroid, foiled by one cloud ... • A German lunar impact observation is now official (and sets a record for the smallest telescope, 10 cm). • New French meteor predictions out. • A bright sungrazer hit the Sun last night (hi-res still; more) • Pictures of July 5 and July 2 (another one) and the lightcurve (from this site) of promising comet C/2009 P1 (Garradd).

Moon vs. Sun: the setting crescent on July 4 (still), Mercury & the Moon and the Moon setting on July 2, the very young Moon from Oz on July 2, two partial eclipses as seen by Proba 2 - which won a price with this - on July 1 and Venus & the Moon on June 30. • Also a slideshow of the lunar eclipse on June 15 from India and a summary plus cloudy Iceland pictures (trip report) of the solar eclipse on June 1. • Epsilon Aurigae is completely "back" now. • A nice ISS Sun transit of May 10. • And a report, another and another from the ALCON event at Bryce Canyon.

Well-hidden solar eclipse starts Saros 156 - the first new one in 83 years

2011-07-01T23:47:00.004+02:00

Only the ESA satellite Proba 2 could observe it as the zone of visibility off Antarctica was as remote as it gets - but the tiny partial eclipse of the Sun early today was special: It marked the beginning of a new solar eclipse cycle, with the number 156; the last one with number 155 had been "born" on 17 June 1928. "We will not have to wait as long for the next new solar eclipse saros cycle to start," explains Jordan Sutton on the Solar Eclipse Mailing List: "just under 47 years until saros 157 is born on June 21, 2058. Saros 156 contains 69 eclipses, starting with eight partial eclipses, [...] followed by 52 annular eclipses, and concluding with nine partial eclipses." No total eclipses are included but that's not unusual. • After months of secret preparations it's now official: The 4th Solar Eclipse Conference will take place in India in December; Details are still sketchy, though. • There is already a paper on the umbra on the June 15 lunar eclipse (two more reports from Turkey and Austria). • On June 30 the Moon occulted Venus in places like Jordan, or there was a close appulse as on La Palma (more, more) or a wider conjunction as in the U.K. (more, more); the day before the Moon was near Mars.

Sky highlights in July (see here, here, here and here) consist mainly of a mediocre evening visibility of Mercury which has already begun, the coincidence of peri- and apogee of the Moon with 1st and last quarter and the occultation of a faint star by asteroid (52) Europa which can be observed in the U.S. • Some more reports also on the stellar occultations by Pluto (more, more). • Two more small moons of Jupiter were announced recently. • The best visuals of the close visit of NEO 2011 MD were shown and linked to here already; more images from June 28 (and earlier), early June 27 (more, more, more), late June 26 (more, more) and late June 25 (more), some news coverage here, here, here, here, here and here (another contender for the worst headline; "asteroid grazes atmosphere" ...) and informative previews here, here and here.

• There is a new object on a comet-like orbit, but 2011 MM4 shows no activity, in contrast to C/2011 M1 (LINEAR). • More previews for Elenin and PANSTARRS (more). • Comet Garradd on June 29 and June 26 (more). • Further criticism of claims that solar activity is about to cease. • A growing gallery of NLC pictures; there was a great show in the U.K. this morning (in motion), also observed from another location (more, more, more); earlier reports from the U.K. on June 29, Canada on June 28 and Poland on June 26 and June 19. • Finally a fine green segment on the Sun - and a weird sky bubble seen from Hawaii on March 22 (another video): obviously linked to a rocket test, but the physics of the bubble remain mysterious.

Tiny asteroid comes to visit Monday: closest approach to Earth surface 12,280 km

2011-06-25T15:23:00.006+02:00

According to the latest calculation with JPL's Horizons ephemeris machine it will be Monday, June 27, at precisely 17:00 UTC ± a few minutes when asteroid 2011 MD - with a diameter of a dozen meters or two, i.e. roughly house-sized - will pass closest to Earth: It will then be only 0.0001247 AU = 18,665 km from the planet's center or about 12,280 km from its surface. As the all-time list of closest approaches shows, this is by no means a record: at least three asteroids that got provisional numbers came even closer - and another one was discovered and then hit us (2008 TC3 of course). Our newest visitor will reach its closest Earth approach point in extreme southern latitudes (in fact over the southern Atlantic Ocean).

The incoming trajectory leg - some helpful animations from different points of view! - passes several thousand kilometers outside the geosynchronous ring of satellites and the outgoing leg passes well inside the ring. One would expect an object of this size - 5 to 20 meters, depending on the albedo - to come this close to Earth about every 6 years on average: a little video shows it moving in the sky this morning. There had been initial speculation that 2011 MD might be old space junk, but this seems practically excluded today. Some coverage here, here (earlier), here and here - and we have already an early contender for the most stupid headline: 5 to 20 meters diameter = "giant asteroid" ... :-)

In other planetary system news we have new data about and a fuzzy pic of centaur Echeclus in outburst, new Afrho data - what that means - from Elenin and an info page about PANSTARRS; there is still some confusion regarding its orbit. • A big bolide in TX & OK on June 20, and yours truly gets quoted re. the Draconids 2011 outlook. • An occultation of a star by Pluto was observed with SOFIA - central flash included - and from the ground, and there will be another one shortly. • A great amateur pic of Mercury showing e.g. the Caloris basin and a montage of Saturn's motion near Porrima.

From the total lunar eclipse 10 days ago report of successful observations with the LRO's DIVINER instrument, another gallery of amateur pictures (more, more and more collections; much more), a German review of what happened, a timelapse video and more selected reports and pictures from the Philippines (more), Nepal (more), India (more and more reports and more, more, more and more pictures), South Africa (a precise lightcurve!), Namibia, Greece (with thunderstorm; alt.; more, Hungary, Ireland, Spain, Austria (unusual timelapse movie; more, more, more, more, more, more, more, more, more, more, more, more and more pics & stories) and Germany (Donauwörth, Garching, Munich, Ulm and Stuttgart), plus a serious and a funny and another weird story on the TLE.

Elsewhere in the Universe a lightbridge in AR 1236 on the Sun where spots were published 400 years ago, a flare & CME on June 20 (video; it was again w/o Earth effects), how Chandra coped with the June 7 flare and yet another (alt.) and another space wx scare story. • The SN 2011dh in M 51 - now at ~12.3 mag. - on June 23 vs. 4 blinking and paired, a June 20 drawing, confusion about the progenitor and how to locate it. • NLCs from Stockholm on June 18 and sky color FX from a Chilean volcano. • An amateur imaging spysats (more). • And another attempt to end leap seconds.

Deep total lunar eclipse enjoyed from Oceania to Europe

2011-06-17T23:36:00.006+02:00

Tons of reports and gorgeous pictures have already come in from many countries, stretching in longitude from Portugal to New Caledonia: There the lunar eclipse of June 15/16 began at dawn while in western Europe it ended at dusk; only in western Asia, the eastern Mediterranean and parts of Africa the complete show could be enjoyed. One way to beat geometry was to follow the eclipse via webcasts of which the one arranged by SLOOH and Google delivered best. This page links to numerous images and reports and fine galleries can be found here, here, here, here = here, here, here, here, here, here and here. Selected pictures from New Caledonia, Australia (gorgeous wide-angle view; more, more, more, more, more and more), South Korea, India (more, more and more), Armenia, Iran (more), Turkey (more), Croatia, Rhodos, Greece (more, more, more and more), Italy (more), Poland, Denmark, Sweden, Portugal, Austria (continued; more, more, more and more) and the UK (no luck).

In Germany the eclipse was right 'on the edge' and visibility of totality depended strongly on your location, let alone the weather conditions. Some reports and image impressions from near Donauwörth (story), Ulm, Irschenberg, Weikersheim (scroll down), Münster, Freising, Leonding, Wasserkuppe, Munich, Vogtland, Plochingen, near Heidelberg, Bonn (little to see; story), Finsterwalde (no pictures) and Stuttgart (nothing; more). Some stories about the eclipse can be found here, here, here, hier and hier (alt.). There were also plans to use the LRO for temperature measurements at high resolution during the eclipse, and a paper just came out on the impact of the Kasatochi eruption on the Moon's illumination during the August 2008 lunar eclipse. Finally a moderately funny German satire about the eclipse and complete nonsense, also here and here ...• Nice pictures of the preceding solar eclipse in Lapland - and a paper on the TSE 10 years ago in Zambia.

In other solar system news another mutual event of Haumea & Namaka was observed and tweeted live from La Palma - the dip was shallower than expected and the live-tweeting of science made news of its own. • There is a new orbit for comet PANSTARRS (scroll down) which would improve visibility even more; since the IfA and the Pan-STARRS project are talking, the comet's got some press here, here, here, here and here. Let's just wait for the orbital calculations to stabilize; meanwhile C/2009 P1 (Garradd) could be fun.

Regarding the Sun, a prediction of low solar activity in cycles 24 and esp. 25 - immediately attacked, BTW - has caused a lot of reporting, e.g. here, here, here, here, here, here, here, here, here, here, here, here, here, here, here, hier, hier, hier and here. • Other solar news addressed the impact of minima (alt.) and solar waves (related paper & story) and ropes; also Proba 2 saw the June 7 eruption (that had no effects on Earth whatsoever) and STEREO the farside of the Sun, plus a long and a short story on solar activity in general.

In deep space the supernova 2011dh in M 51 has brightened to about 12.7 mag.! A picture of June 7 and a paper and another one and a report and another one on the progenitor. • Finally a possible nebula discovery by an amateur astronomer - and NLCs during the lunar eclipse spotted in Austria of all places.

There could be a bright comet in the sky ... in April 2013

2011-06-09T21:26:00.004+02:00

This is just a pre-pre-warning with many caveats ... but if the first orbit for newly discovered comet C/2011 L4 (PANSTARRS) holds, it could put on quite a show when the visitor reaches a perihelion of only 1/3 AU in April 2013. A first visibility analysis by this blogger sees the comet very close to the horizon in the Northern hemisphere just after perihelion - when it may reach 2nd or 1st magnitude or even better - while it's better visible in the weeks before and right up to perihelion in the Southern hemisphere. Once the orbit stabilizes, these calculations will be repated in greater detail, and then it's up to the comet's brightness to perform. If it does work out as the standard formula implies, you read it here first ... • In other comet news the state of Elenin (and one more anti-BS article), new comet C/2011 L3 (McNaught) and continuing observations of the outburst of 174P/Echeclus. • On June 15 a faint asteroid will visit a bright star in Leo, and 2009 BD is feeling radiation pressure. • Opinion about the 2011 Draconids is still wildly split: Will there be hardly any meteors or 600 per hour or 1000 per hour ...?

Regarding larger bodies in the solar system the next Transit of Venus is (less than) a year away now, spawning this website and outreach ideas. • A close-up of Saturn & Porrima and another view with some Chronian satellites, too. • More previews of the June 15 total lunar eclipse here, here, here and here - and remember my old advice for the optimum experience! • Pictures of the June 3 lunar crescent here, here, here and here. • From the Midnight Eclipse the best movie (almost hypnotic ...), another one, one from Proba-2 and more coverage and image collections here, here, here, here, also great pictures from Norway (more) and Iceland. • A big solar eruption on June 7 (more and more animations and coverage here, here and here) led to some expectations for the Earth (see also here, here, here, here and here for some hysteria) that didn't materialize (see also here, here and here): Better look here first (and the U.N. will save us anyway :-). • Also the Sun on May 31, some wave phenomena and spectroscopy - and more details about Nova Sco.

The supernova 2011dh in Messier 51 is at about 13.4 mag. in the visíble right now as collected pictures & photometry and esp. visual estimates show. We have a gallery, calls by the Weizmann Inst. and Palomar Obs. for yet more (early) pictures of this apparent type IIb SN and selected pictures of June 7 (more), June 6 and June 3 (explained; more, more and more). As it has turned out this blogger played a role in the obtaining of the first-ever spectrum of the SN (also 'discussed' here and in the tweets here, here and here). There is a potential identification of the SN progenitor (easily visible in a public HST image of M 51), and the SN was seen in X-rays, by Swift's UVOT and in radio. Finally some more general coverage of the SN 2011dh here, here, here, here, here, here, here, here and here. • Finally a cool video with NLCs and aurora shot June 4 in Minnesota - and extremely detailled pics of the ISS & OV-105, also hailed here.

13th mag. supernova in famous Whirlpool galaxy M 51 - widely observed before even official ...

2011-06-03T18:07:00.005+02:00

Normally there is an IAU Circular, spawning alerts through various astronomy news services, leading to observations - but with a supernova discovered in the night June 1/2 in the famous galaxy Messier 51 it was very different. As this blog 'goes to print' object "PSN J13303600+4706330" still hasn't been announced officially as a supernova, yet the web is full of great pictures and other data, including spectral information confirming a type II SN. There are early confirming pictures here, here (triggered by yours truly last night and spreading quickly), here, here (in the order in which I learned of them) and several here. Apparently the supernova was already there on May 31 but seems to be absent on May 30; here is also the regular view of M 51. • There is also a new Nova Scorpii, also discussed here (picture). • Epsilon Aurigae is almost back & in conjunction with the Sun now. • The H-Alpha Sun today, prominences on May 25 and ideas regarding dark sunspots.

The "midnight solar eclipse" was widely observed in northern Europe and also in Russia and N America: more previews here, here and here, pictures from Russia here and here, from Finland here (with sunspots!), here and here, from Sweden here and here, from Norway here, here and here, from Iceland here, here, here and here (later) and from Alaska here - picture collections can also be found here, here, here, here (related article) and here. • The 1-day Moon after the eclipse was imaged in the U.S., Mexico and Brazil. • More previews of the June 15 lunar eclipse here, hier and hier. • The color of the full moon enhanced. • Saturn at Porrima.

The morning planets and the Moon on May 31 from Poland, May 30 from Argentina, May 29 (and other dates) from South Africa and May 28 from California and Australia. • Centaur 174P/Echeclus in outburst, and image of 2009 P1 (Garradd) (which should be bright next year), new comets P/2011 JB15 (Spacewatch-Boattini) and C/2011 K1 (Schwartz-Holvorcen), Elenin still faint and still orbited by idiots - and anoth comet plunging into the Sun Mai 21st. • A fly-by by 2009 BD and a bolide in Georgia on May 20. • A little audio introduction to NLCs. • And glorious pictures by D. Caxete of the ISS & Endeavour in front of the Sun, plus some trails of the two later - and a video of the reentry over Yucatan.

June 2011: three eclipses - 2 partial solar, 1 total lunar - in one month!

2011-05-31T17:10:00.003+02:00

This triple eclipse headline is literally true for the Eastern Pacific, where June begins and ends with partial solar eclipse (for the remainder of the planet and UTC the 2nd solar eclipse falls on July 1st already and hardly anyone will see it in any case). These - and a few other - highlights of this month:

June 2/1 (because the Int'l Date Line is crossed): Partial solar eclipse in the far North, with the greatest magnitude (mag. 0.6) in Russia.
June 14: Saturn just 1/4° from bright star Porrima; the two are forming a nice 'double star' already now!
June 15/16: Total eclipse of the Moon, best seen from E & S Africa and W Asia (websites from RSA, Pakistan and India) but also a little bit at the end from Central Europe.
June 28: Dwarf planet Pluto in opposition at 14th mag. in 31 AU distance.
July 1: Partial solar eclipse just off Antarctica - and nowhere else. D'uh!

Meanwhile the morning planets show is coming to an end: some nice vistas of May 31 from Turkey, of May 30 from Germany (it's tough ...), of May 29 from the U.S. (more), of May 26 from Australia, of May 23 from S. Africa, of May 22 from Malaysia, of May 20 from Iran and Australia, of May 19 from New Zealand (more), of May 18 from Greece and Australia, of May 17 from high over Australia (at 39,000 ft!), of May 16 from the U.S. and Tahiti and of May 15 from Cyprus. • Also a Mars close-up from May 26 (taken in Germany - in daytime) that shows quite some detail despite just 4" diameter and May views of Saturn's storm which was also studied in the IR.

In other news unusual views of the Moon: in polarized light, used as a diffracting edge, in extreme libration and with impacts by 3 Eta Aquarids and one Quadrantid (some background on this kind of observation here and here). • Images of poor comet Elenin of May 24 and May 16 and what the future may bring (and what not). There are also a new comet C/2011 J3 (LINEAR) (more) - and pre-discovery observations (and non-observations) of C/2010 A2 (LINEAR). • Some bizarre (non-)impact stories: another megacryometeor mystery and weird circumstances of the Dryas (more) and Chiemgau non-impacts.

• From the Sun May prominences (from every day from May 19 ... 26), the May 25 full Sun in H-Alpha and a May 9/10 CME movie, aurora over Tasmania on May 28, plus preventing space storm damage on Earth - and a weird scene from an art exhibition (headline - not connected to the pic - NSFW) ... • A star's proper motion in 110 years documented. • The first NLC sightings of the year are in; see also here. • Some post-processing of ESO movies showing Paranal rotating in a fixed Universe. • A rare timelapse movie of geostationary (or rather not so stationary!) satellites. • An Endeavour water dump (more). • And the ISS & Endeavour in front of the Sun with veeery high and not quite so high resolution (one more) - this low-res movie shows how fleeting these 'transits' are.

Planet show continued: the Venus/Jupiter/Mercury trio

2011-05-15T16:02:00.005+02:00

As they say: "The cosmic ballet goes on," with the morning planets moving into new shapes every day. Further impressions - now with a Venus/Jupiter/Mercury triangle - of May 15 from Australia (scroll down), of May 14 from South Africa, Malaysia and the Philippines, of May 13 from South Africa and Australia (more, more [details], more), of May 12 from the U.S. (more, more), Canada, Poland (at 50° North!), Israel, Iran and Australia (more, cloudy) and of May 11 from Uruguay, Canada, the U.S., the Canary Islands, Spain, Italy, Austria, Poland, Israel, Indonesia and Australia. • Plus a rare drawing of Saturn from May 12.

In other news new faint comets C/2011 J2 and C/2011 H1, plus the demise of the latest SOHO comet (also an animation [bottom]; more, more). • Dubious stories about a meteor bang w/o a meteor and a meteorite crater w/o a meteorite (more). • A paper on the high solar activity in Nov. 2003 and a new warning system from Germany. • Pictures of SN 2011by of May 12 (another close-up), May 7 and May 4 - while T Pyx is near its peak now. • The ISS on the Sun. • More coverage of the new big sky mosaic (final graf) here, here, here and here - and all three mosaics in direct comparision. • And how amateur astronomy has benefited from the unrelenting advance of technology.

Great morning planets show seen around the clock around the world

2011-05-10T18:51:00.003+02:00

The line-ups & conjunctions of four naked-eye planets just west of the Sun - see also here, here, here, here, here, here and here plus an animation; a close Venus/Jupiter conjunction on May 11 & 12 is the next highlight - have been a great show in Southern and extremely tough to see in mid-Northern latitudes. Here are impressions of May 9 from Argentina, California and Australia, of May 8 from Austria, Jordan, Turkey and Australia (again), of May 7 from Chile, Italy, Austria (daytime close-ups!) and Tasmania, of May 6 from the U.S. and Austria, of May 5 from Argentina and Australia, of May 4 from Australia, of May 3 from Australia, of May 2 from Chile, of May 1 from Chile (cropped), the U.K., Australia (again and again) and the Philippines, of April 30 from Florida and Venezuela and of April 29 from New Zealand.

In small bodies news a big paper on how to get asteroid shapes from lightcurves and stellar occultations, the funny lightcurve of 2010 TU5, another 2005 YU55 press release (picked up here and here) and a long German story on NEO defense. • In Poland a meteorite hit a house (more, more and more) and a new mineral - named krotite - has been found in a meteorite. • There is a 3rd mag. Kreutz comet in this May 10 SOHO image at 7 o'clock (earlier today), comet Elenin on May 4, May 3 (more) and more dates, with absurdly high, optimistic and pessimistic predictions around, and new comet websites with hot visual estimates and Argentinian pictures.

In other news The H-Alpha Sun on May 3 and a geostorm on April 30. • T Pyxidis might be fading after brightening (another report). • SN 2011by has risen to 12.3 mag. as many confirm. • Eps Aurigae is now in egress with the eclipse soon over - and a lot of science results left behind. • Two more fine sky timelapse movies from the Canary Islands and Greece. • Close-ups of NanoSail D here and here, a Brasilian reentry video, explained here and here (more and more on the satellite), a Russian sky show after a launch, explained here and hier - and a close-up of USA 129, a U.S. spysat.

Four planets (and the Moon) in action in the May morning sky - and a nice supernova!

2011-04-29T22:48:00.008+02:00

While the play of the planets - Mercury, Venus, Mars & Jupiter - is best seen from moderate Northern and esp. Southern latitudes, the supernova in the Big Dipper is ideally placed for Northerners. It was discovered very early, at 14th magnitude, and could rise to 12th - which would be pretty rare - during the coming week. Of all planets still only Saturn (a nice April 19 pic and several of the ongoing storm) is easily seen from everywhere, while the other four naked eye planets are so close to and west of the Sun that you need a either a steep ecliptic (like in this Australian view from April 26) or binoculars to see them and esp. the various conjunctions of between them, listed below. Some key dates:

April 30 & May 1: The waning crescent Moon joins the morning planet line-up - simulated April 30 sky views for Australia and later California and the view on May 1 for Germany. On May 1 Mars is 21' north of Jupiter.
Around May 3: Possible 12 mag. peak of Supernova 2011by in NGC 3972 in UMa; here are the Chinese discovery picture and a color view.
May 6: Peak of the Eta Aquarids, like the planet show something great only for Southern observers.
May 8: Mercury 1.5° south of Venus.
May 11: Mercury 2° south of Jupiter and Venus 34' south of Jupiter (thus a planet trio).
May 18: Mercury 1.3° south of Venus.
May 21: Mercury 2° south of Mars.
May 23: Venus 1° south of Mars (another planet trio, with Mercury).
May 31: The Moon is once more close to the morning planets.

In other news comet Hale-Bopp has been seen at 30.7 AU from the Sun, a new distance record, there is a 2nd paper on the Scheila outburst (discussed here, here, here and here together with the first), and the outburst of comet 240P is ongoing, in different phases. • Asteroid 2011 HS showed a wild lightcurve (pics one, two and three) and is probably tumbling while features on Lutetia has been named. • A meteorite shower helped finance a school, while meteorite collectors claim they are good guys. • A report on a reference observation for (not) understanding a 1963 TLE, the Sun's AR 1195 on April 23, yet another huge sky mosaic (discussed here; two from 2009 were compared here), a sunset movie with several green segments - and the ISS in recent days, in high resolution, also animated and as trails.

Solar activity up sharply - and spots so big you can see them on simple sunset pictures!

2011-04-25T00:03:00.005+02:00

Solar activity is now really taking off, and the monthly sunspot number values are up sharply in the NOAA diagram here - but since cycle #24 took off so late (as did important precursor events) the prognosis is still for a rather shallow maximum around 2013. There was a lot to see in recent days (and this forum alone is overflowing with images): On April 23 AR 1195 was so big that it appears inadvertendly in this simple sunset picture by yours truly! Also various hi-res H-Alpha scenes and AR 1193 in hi-res on April 20, the white light Sun on April 17, more sunset spots on April 15, a great prominence animation of April 10 and R.A.S. press releases on a coronal mass ejection on March 20, the big solar flare of Feb. 15 (also discussed here and here), the birth of a sunspot, analysis of SDO data and the solar eruption process (also discussed here); at the meeting where these came from the chance of a new Maunder minimum was also discussed. There is also a weird paper on how bacteria in India enjoyed the 2010 annular eclipse, while the webzine TOTALITY! #10 has some 40 pages on the 2010 total eclipse, including a report by yours truly.

In other solar system news here's Saturn on April 17 and April 16 and the - again very big - full moon of April 17 rising and setting. The tables here are helpful in finding future perigee and apogee full moons. • A paper and another one on carbon monoxide in Pluto's atmosphere, also discussed here, here, here, here, hier, hier and hier. • Of the 2011 GP95 NEA fly-by a newer and an older video - and another interesting case coming up on June 2! • Regarding comets, a mini-video of 249P in STEREO's FOV, ideas on Main Belt Comets and the poor show so far by comet Elenin (which also got an article and a FAQ debunking related BS). This blogger also became aware of this 2007 report from the ISS where sensational comet McNaught was apparently only seen "by chance": This is a scandal, plain and simple!

Beyond the solar system recurrent nova T Pyxidis has now settled around 7th mag. after brightening steadily and may yet reach 6th mag.! There are also some spectra - and IR photometry of Eps Aurigae. • The STEREO spacecraft has found a lot of new variable stars, also hailed in this and this press release. • Back on Earth three more great timelapse videos: from Tenerife (mentioned here; the light pollution is quite obvious), Mauna Kea (night of April 23 - great mountain shadow triangle and lens flares, also hailed here) and the continental U.S. (with a moving dolly). • What the AIM satellite found out about noctilucent clouds. • The ISS, imaged from Witten passing high on April 24 (parallel shot from Bonn) and rising vertically on April 23 by yours truly. • The NanoSail D is still up and seen occasionally (see also the Cosmic Mirror #341 header), sometimes pretty bright - and the reentry may not come before July. • And a long table of Easter dates: While having E Sunday on the 2nd-latest date (April 24 as this year) is twice is frequent as hitting the very last day, the two 24 Apr dates framing 2011 are in 2095 and were in 1859, the two 25 Apr dates are in 2038 and 1943, resp. - small number statistics.

50-meter asteroid close to Earth now - with 2 mag. brightness changes

2011-04-15T19:59:00.007+02:00

As this posting goes online, 50-meter NEA 2011 GP59 is closest to Earth at 530,000 km, one week after its discovery by an amateur-run sky survey in Spain. This is (or rather was; the optimal visibility was yesterday, with 13 mag. as compared to 14 mag. now) the best NEA Earth visit in several years, and the object has been observed a lot in the past days: Of particular interest were strong brightness fluctuations every four minutes, due to the - probably non-trivial - rotation of the elongated body.

• This is a NEA visit worth of some headlines, but most aren't as small ones come close all the time. The November visit of big 2005 YU55 is a different case, of course. • An asteroid on a long-lived horseshoe orbit 'around' Earth has been identified (another and another press release; some coverage here, here, here and hier. • A story on shady meteorite deals [alt.] has been attacked. • And yet another U.S. fireball that may have dropped.

Comet C/2011 C1 (McNaught) looks like a tiny Hartley 2, making it interesting for photographers: April 10 [alt.], April 5 and April 3 pictures. • The expectations for comet C/2010 X1 (Elenin) are still not clear (another and another story, a light curve with Russian debate - and it won't destroy Earth ...). • New comet C/2011 G1 (McNaught), more on the funny Holmes paper (more and more), a page with light curves and a paper on main-belt comets.

Tonight from 19 to 21 UTC photograph the Moon and the Aristarchus region in particular which was the location of a famous Transient Lunar Phenomenon in Oct. 1963. (And if you check the ground-to-air of Apollo 11 at 076:57:07 and 077:12:51 you see that an alleged Aristarchus TLP even played a little role in the famous mission and also featured in sect. 7:17 of the astronauts' debriefing.)

Great - literally! - Moon mosaics of April 10 (also 2 details by someone else), April 9 and April 8, the young crescent of April 4 from Germany (more) and Portugal, plus the waning crescent of March 3 from Cairns. • The Jovian moons in SOHO's view (animated; STEREO had a better view in the past). • And Saturn on April 3 and - hold your breath! - March 28!

More action on the Sun on April 11/12 (CME video), April 11 (H-Alpha edge), April 10 (hi-res mosaic; also a detail; the fish was gone soon :-), April 6 (prominence video); also various April prominences, a March SDO timelapse movie and March 21 H-Alpha hi-res views. Plus the general rise in solar activity, and the little ice age. • Lots of solar eclipse stories in the Feb. 2011 Practical Astronomy, a great totality earthshine from 2008 - and total eclipses of the next 50 years in one map.

T Pyxidis is in outburst, the first time since 1966 (more, more and mehr). • The brightness of Eps Aur is rising steeply now (also the 8th newsletter). • Also stories on SN 2011az and the Z Cam campaign by the AAVSO. • And an article on a Deep Sky meeting in Linz.

A collection of great aurora pictures from the AuroraMAX camera system (discussed here), an aurora timelapse from an airplane (discussed here) and yet another aurora video. • Without aurorae night timelapse clips from India and South Dakota. • And the analysis of the Iceland volcano ash [Deutsch] over Europe a year ago.

Saturn reaches opposition, brightness of rings may surge

2011-04-03T00:38:00.002+02:00

About 24 hours from now - around 0:00 UTC on April 4 - Saturn reaches the opposition point to the Sun: several effects conspire now to brighten the rings, and some observers claim the phenomenon is already detectable. Some recent amateur observations of March 30, 25, 23, 22, 21/22 (with spokes), 21 and 20, plus a mid-March Hubble image with more storm detail. • Other sky sky highlights in April include Uranus' crossing of the celestial equator - but this is purely academic as the planet cannot be observed right now. And the visibility of all planets except Saturn is very poor to non-existent this month. There is another opportunity to observe a pretty young lunar crescent on April 4 for Northern hemispherians, however.

A look back at Mercury (and Jupiter) low at dusk on March 23 (Germany), March 22 (AZ and Austria), March 19 (Germany: Cologne and herten and March 16 (Sweden), plus a note on Jupiter's SEB return. • Lots of fine pictures of the March 19 perigee full moon are linked here, some collections included.

In small bodies news an analysis of Elenin (still mildly optimistic for fall) and a March 25 picture, some jets of 29P in outburst, new comet C/2011 F1 (LINEAR), a funny paper on the Holmes outburst, a serious paper on the Scheila outburst, a bolide on March 23 (more), a claim of more fireballs in Northern spring and a call for observations regarding a possible Southern stream.

From the Sun a nice March 27 H-Alpha mosaic, SDO action on March 24, various March pics, a claim that maxima are always double and a good solar April fools joke (more space-related jokes of note here, here, here, here, here, here, here, here, hier, here and here :-). • Some light intensity data from the 2009 TSE in India and a contemporary documentary (part 2 with the actual event) about TSE expeditions in 1973.

Elsewhere in the Universe the brightening of Epsilon Aurigae has begun. • A deeep image of the Virgo cluster. • Excellent aurora videos from Norway have turned up on Vimeo here, here (background) and here, also great stills from Norway again and Finland (another trip report, a big panorama and an allsky series). • A fine green flash and another one through a tree. • And finally the ISS in front of the Sun in new images here (with spots), here and here.

If you know your full moon you will note it is bigger than often on March 19!

2011-03-17T23:14:00.004+01:00

As about everyone will have heard by now, the full moon of March 19 coincides with perigee and has thus the largest angular diameter in years. So will you note that fact by looking at it without optical help? Many bloggers, stories and even a NASA video tell you that you cannot and will notice a particular size of the March 19 full moon only because you either knew about it or because the moon illusion close to the horizon helps. But this is simply not true! Obviously these people have never tried for themselves - but this blogger did, inadvertendly and without knowing anything about its distance, when he watched the Feb. 17 full moon high in the sky and noted its unusual angular size. Then checking the ephemeris, the reason was obvious: perigee was close and the (topocentric) distance only 359,000 km! The full moon of March 19 will look exactly like that to the eye, so prepare for a beautiful show - and use it to e.g. try to see as much surface detail as possible with the naked eye. And if weather is bad, don't worry: The April full moon will be as close again as in February. So enjoy the show and forget about ridiculous articles like this or this, claiming links to natural distasters: even NASA responded; more rebuttals are here, here, here and here.

The Sun made more headlines in the past 10 days, e.g. with a fine Aurora on March 10 in Northern areas following a flare late on March 9 (more, more, more and more), lots of sunspots in white light on March 8 and action also on March 7 (wavelength crossfade animation, fast CME, lotta flares). There were again general articles on solar activity and even an OpEd by science advisors - with the strange claim that "the severity of future [solar] storms could be much greater than those experienced in recent decades". And the SDO saw a partial eclipse by the Earth; the fuzzy limb is caused by the latter's atmosphere. • Planet-wise some amateur pictures of the continuing huge storm on Saturn of March 14, March 12 and Feb. 23 (also animated) and Cassini close-ups of March 13 and Feb. 25/26. The return of Jupiter's SEB continues, and the planet met the Moon on March 7 (more and more) - when an amazing mosaic of the crescent was obtained by a Russian astrophotography wizard. The evening visibility of Mercury (close to Jupiter), seen on March 16, March 15 (more, more and more), March 14 (more, more), March 13 (more and more), March 11 and March 7/8; many more and still more pictures.

In other news excitement is building for a large asteroid's Earth visit in November while harmless Apophis is observed again after a gap, themes for features on Lutetia have been approved and the spectra of the meteorites from asteroid 2008 TC3 resemble certain dust around stars. Also a fireball in Canada and a distant picture of Hartley 2. • The long eclipse of Epsilon Aurigae should end now! • A cool video & picture series of green flash of the setting Sun. • And finally the space shuttle Discovery crossing the Sun on March 7 (more) and the ISS and Discovery crossing the Moon the same day. Plus an impressive (this blogger saw it in binoculars: like a little comet dust tail!) water dump by Discovery on March 8 as an animation and still (more plus story); the phenomenon can also be seen in this wide-field animation and this still; it may also cause the fuzziness of the trail here. And finally some ISS/Discovery trail pairs and a very long exposure, some hi-res views and many more linked from this article by yours truly.

Mercury evening show - aided by Jupiter - sky highlight in March

2011-03-07T21:07:00.007+01:00

The best evening visibility of Mercury - for the Northern hemisphere, in 2011 - has just begun: The planet is still very close to the Sun but also very bright. In the coming days it'll fade but increase its elongation from the Sun (until the 23rd) - and on March 15 it will be only 2° from Jupiter which will help locate the elusive planet (which will receive its first artificial orbiter with MESSENGER on the 18th, by the way). This is clearly the main event of March 2011; for more see this, this and this story. • There were already nice constellations in recent days: the Moon & Jupiter on March 7 (Germany; U.K., Moon close-up)and March 6 (U.K.; more, Moon close-up, Austria, Moon close-up, Germany, Moon close-up, more), Jupiter close-up on March 5 and Moon & Venus on March 1 from the Philippines, India (more), Germany, the Canary Islands (daytime), the U.S. plus more. Also Saturn on Feb. 23 (movie).

In other news Comet Hartley 2 is still around but tiny, Elenin is still there, as are many other comets. • A meteor network, yet another obit for the Dryas impact claim, 19 NEAs in one night with PanSTARRS and more NEA studies. • The Sun in white light on March 7 and March 5, in Calcium light with a plane on Feb. 27, and a huge prominence on Feb. 24 (more, more, more). • Also a quick paper on the 1st X flare of the cycle, some ideas about weak cycle 23 (more, more, more, more, more, more, more, more, more, more, more and mehr) and numerous space weather stories here, here, here, here, here, hier and hier. And this is just what's flooding the net after a little action on the Sun ...

• Talking about the Sun, the SDO saw a funny partial eclipse on March 4 (more, more, more and more), there is a story on a little known Japanese eclipse flight during the last total eclipse in July 2010 in an Air Tahiti Nui magazine on PDF pages 33-34, and the weather analysis for the next total eclipse in Nov. 2012 in Oz has been updated. • The last flight of Discovery STS-133 has been amply documented by astrophotographers like Legault; other work is linked from this article. Also hot pics of Discovery and the ISS after undocking this evening from Germany (more and more) and one orbit later from the U.K. • Only sporadic observations of NanoSail are being reported, such as occasional flare pics and vids. • The AAVSO has received observation # 20 mio. (more). • And Leif Robinson has died (more).

Mighty flares, few aurorae (yet) - and lots of media confusion

2011-02-19T16:09:00.005+01:00

It had to happen, after this long solar minimum: The moment activity picks up - with several M flares and even one with X-class in mid-February - the media go overboard with excitement, science institutions jump on the wagon to tout their related work, and it's up to sober bloggers to put it all into perspective ... Events in reverse oder: • There was an M flare on Feb. 18, and the sunspot groups 1161 and 1162 are causing waves of ionization in our ionosphere and should be watched carefully.

• The X-class flare on Feb. 15 (more and more) from AR 1158 was first thought to be capable of causing great effects (like in this report ...), but it didn't happen and predictions remain difficult, as e.g. this analysis points out (earlier) - more coverage here, here, here, here (earlier), here, here, here (earlier), here, here, here, hier and hier. • The M flare on Feb. 13 was covered e.g. here, here and here - and at the time was not the biggest of cycle. • Regarding solar activity also stories on the worldwide CALLISTO network and the role of IBEX as a monitor.

In other news a movie of a lunar flash (more details) recorded on Feb. 11, a pessimistic Elenin analysis (recent observations point to only +6 mag. at max.) and fireballs in Philadelphia (more) and Chicago (more). • Amateur analysis of Haumea and its lightcurve. • And a speculative paper on "a jovian mass solar companion in the Oort cloud" makes headlines (more, more, many more, mehr and mehr), so that eventually NASA had to comment on the (non-)issue ...

Closest non-impacting object in our asteroid catalog came by, changed direction by 60°

2011-02-13T18:25:00.004+01:00

Asteroid 2011 CQ1 made a record close Earth approach on February 4th, 14 hours after its discovery. It passed to within 0.85 Earth radii (5480 km) of the Earth's surface: This 'flying sofa', only about one meter in diameter, is the closest non-impacting object in our asteroid catalog to date. Prior to the Earth close approach, this object was in a so-called Apollo-class orbit that was mostly outside the Earth's orbit. Following the close approach, the Earth's gravitational attraction modified the object's orbit to an Aten-class orbit where the asteroid spends almost all of its time inside the Earth's orbit. The close Earth approach changed the asteroid's flight path by about 60°. There are nearly a billion objects of this size and larger in near-Earth space and one would expect one to strike Earth's atmosphere every few weeks on average where they airburst; only rarely do even a few small fragments reach the ground.

In other small bodies news a paper describes the outcome of NEOWISE, the (full) mission of the WISE observatory. • Asteroid transits over planet disks are more frequent than one might think. • Rob McNaught's 58th comet has been discovered, also pics of a small comet near a galaxy and of Hartley 2 near M 50 (more). • A paper on human perception may be of relevance for visual meteor observers. • A nice fireball over Italy, also discussed here. • Debate over the first impact crater in China and the meaning of the Kamil structure for impact physics. • Regarding larger bodies, the storm on Saturn on Feb. 6 and Feb. 5 (plus a progress report, rather old Keck pics of the SEB revival on Jupiter and Jupiter & the Moon on Feb. 6.

In solar research we celebrate one year of the SDO in orbit. • Results on CME ripple structures and particle acceleration near Earth. • The two STEREO s/c are now seeing the entire Sun, als also hailed here, here, here, here, here, here, here, here, here, here, here and hier. • How LOFAR saw the solar eclipse on Jan. 4 in radio. • A new sequence for SN 2011B. • A bright outburst of star (with a crazy name) and an outburst of Z Cam. • New insights into Eps Aur. • Amateur imaging of a z=6 object. • Some images of NanoSail D (also here and here), plus the flare geometry. • And finally, returning to SDO's launch a year ago, a new kind of halo effect triggered by its rocket.

The hunt is on for NanoSail D: some sightings, no major flares yet

2011-01-31T22:46:00.006+01:00

The initial report of little solar sail NanoSail D's release from the FASTSAT were wrong ("Keinerlei Kontakt ..."), but a month later the nanosatellite spontaneously ejected after all and deployed its sail as planned, with the battery draining a few hours later ("Dem Nanosail ...), also as planned. Now an inert satellite experiment it's up to amateur astronomers to track its behavior and there are even prizes waiting ("Fotowettbewerb ...") for the best images submitted here. Links to successful sightings & pictures can already be found here (in the header): some trail images with no obvious large flares from Iridium-style specular reflections (although this one from Finland seems flaring) and visual reports, usually between +6 and +7 mag. It's all a question of attitude, and future surprises are possible. The satellite should reenter between late March and May; visibility predictions are offered e.g. by Heavens Above; hit "Next" repeatedly for future viewing windows. • Observing the ISS transit the Sun in the Philippines. • NLC space image sequence and brightening trend claim. • A nice solar Omega (more), the Moon in 3D and on 5 subsequent days.

A supernova of 12.9 mag. can be seen right now in NGC 2655: photometry, images, visual impression! • There is a Nova Sgr 2011 at 11 mag. • FS Aur had a little outburst: alert, observations, context. • A poster with new CHARA pics of Eps Aur from the 217th AAS Meeting, a long human interest story on the lead observer, a paper on the campaign and the star's status. • On Feb. 6 we will see the whole Sun as the STEREO s/c span a 180° angle, a coronal hole may cause aurorae in early Feb., new insights from THEMIS, a double eruption on Jan. 28, a kinky CME on Jan. 13, better TSI measurements (alt., more) and nice Big Bear images. • From the Partial Solar Eclipse a hot MeteoSat movie, more fine images here, here, here, here (bottom), here and here, another gallery, an animation, a video, TV reports from WDR (w/yours truly), SWR and Rosenheim24 and a summary. Also the 2010 TSE as a partial from Tahiti and the Dec. TLE from Scotland and in another collection.

A fireball over Southern Germany was nicely imaged and led to a meteorite hunt; reports from other fireballs here and here (more). • Details on the Draconids this year. • Comet 29P is in outburst again: pictures here, here and here. • Elenin is still faint (more). • A new comet C/2011 A3 (Gibbs) (more). • Pics of Hartley 2 (and DS objects) from Jan. 30, Jan. 28, Jan. 26 and other dates, the SOHO 'comet storm' (over) and the 30th BAA comet magazine (PDF). • The Scheila outburst seems over, many observed a star occultation by (144) Vibilia and will try to see one by TNO Quaoar early on Feb. 2. • Hi-res images of Mercury 2008-10. • Venus & the Moon on Jan. 30 (more). • Jupiter in mid-January - and the 2009 impact explained (more, more, more). • Saturn (and its mighty storm) in amateur pics of Jan. 31, Jan. 29, Jan. 28, Jan. 26 (more), Jan. 17 and earlier and on Cassini pics of Jan. 21, Jan. 15 and Dec. 24 - Saturn's march towards opposition in April is also the lonely highlight of February (mehr, mehr und mehr).

Deep partial solar eclipse yields countless spectacular images

2011-01-09T23:52:00.006+01:00

The partial solar eclipse of 4 January 2011 - which just missed being annular but was seen as a ring from space in Low Earth Orbit - may be one of the best-observed in history as it included densely-populated Europe. While many had to struggle with clouds, those often added to the beauty, plus the Sun could be caught in eclipse at sunrise in some European countries. The overall result is an unfathomable wealth of pictures in all kinds of places on the web: Here is a huge & growing link collection while fine images by indiduals and wire services alike have been collected e.g. here, here, here, here, here, here, hier, hier, hier, hier and here and news stories can be found here, here, here, here, hier, hier, hier, hier, hier, hier and hier (and for the record a lot of maps, graphics and previews of webcasts). Now to many individual photo galleries and reports:

In Germany yours truly chased the eclipse to Aachen with a TV crew; more pictures from the region are linked from there. Also selected pictures from Emmerich, Bochum, Oberhausen, Cologne, Bonn, Stuttgart, Rosenheim, Kaufering, Irschenberg, Munich (more, more), the Black Forest (more, more), Waiblingen, Wetzlar, Bentheim, Heidelberg, Pforzheim, Weimar, , Jena and Saxony (more, more, more and more). We also have pictures taken with a PST, photometry of clouds (more, more and a cloud picture series) and more reports from Germany here (a lot!), here, here, here, here, here and here. And from a train from Germany to Austria!

From other countries a lot of reports from Austria (more, more [more], more, more, more, more, more, more, more, more, more, more, more, more, more, more, more, more, more and more), from Switzerland (more), the Netherlands (lots more in this gallery, e.g. this, this, this, this and this sunrise shot), from Belgium (more), Spain (an 'Omega' sunrise; see here and here; more), Gran Canaria, the UK (more, more, more, more, more and more), Denmark, France, Italy, Sweden (more and more), Greece, Hungary, Romania, Israel, Egypt, Oman (with the ISS spoiling the view; discussed e.g. here and hier), Russia (more, more and more) and India (more and more). Oh, and from Finland a radio(!) picture.

And after the eclipse the Moon came back into the evening sky - and was well observed around the world one day later (more), 2 days later, 3 days later (more), 4 days later and 5 days later i.e. this evening (more) - also a collage of the 3, 4 and 5 days old Moon. • Talking about the Sun there's again excitement about a potential route to solve the coronal heating mystery, this time via spicules: press releases and stories here, here, here, here, here, here, here, here, here, here, here and here. • Also the SDO is studying the inner corona, and the Calafate eclipse from last July is shown here on page 12.

In other news comet P/2010 V1 next to a globular cluster today and on Jan. 5, Hartley 2 on Jan. 1 - and early thoughts about Elenin this fall. • Asteroid/comet Scheila on Jan. 1; more stories here and here. • A call for photometry of three Vestoids (and new insights into Vesta itself). • Jupiter on Jan. 2 and Dec. 23 - and the SEB revival in one image covering Nov. 8 til Dec. 30. • Jupiter and Uranus on Jan. 3, just now joined by the Moon. • The storm on Saturn observed frequently by A. Wesley. • Moon, Venus & Mercury on Jan. 1. • And finally an animation of a persistent train of a 2011 Quadrantid; more on their peak (which didn't quite reach ZHR=100, it seems) here, here and here.

Deep partial solar eclipse & Quadrantid peak & Uranus @ Jupiter all coincide on 4 January 2011

2010-12-31T17:27:00.014+01:00

This monthly preview is easy: Everything of interest happens within a few hours on Tuesday, January 4, 2011! • For the third time Jupiter and Uranus meet within 1/2° (some list the closest approach for Jan. 2, though). • The Quadrantid meteors peak around 1:10 UTC when the ZHR might briefly surpass 100 (more previews here, here, here, here and hier). Of all the major showers of 2011 this is the only one without severe lunar interference! • A few hours later a deep partial eclipse of the Sun can be seen in Europe and around: more, more, mehr, mehr, mehr and mehr. As usual there is an official health warning, once again blown out of proportion in the media ("watch only on the web!") - a very bad move for public education. Anyway, webcasts - from Spain - are announced here, here and here. The year 2011 is particularly rich in eclipses (more, also a specific U.K. outlook); more on the coming months and January in particular. Also a look ahead in physics - and several looks back, in case anyone cares ...

The total eclipse of the Moon preceding the PSE was already covered - with maaany links - hier and hier. Also thoughts on its brightness, a SQM graph, some individual reports here (with a fast movie), here, here, here and hier, further selected pictures from Germany, Tenerife, Costa Rica (story), Nicaragua (story), the U.S., Canada and the Philippines. Plus a picture collection (much more), all-sky pics with bolides during totality, a video from Cumbria, the stabilized version of the famous great animation (by Castleman), a more jerky animation and HD stills of the eclipse over the shuttle. Some media reports are here, here, here, here, hier and hier, story collections hier, hier and hier, and report on how Chang'e 2 coped with the shadow. And finally the "rare solstice eclipse" misunderstandings are still around (just look at the bizarre comments here when I pointed out that for most it wasn't one anyway - and that the next case is only one Meton away), and there was even more bullsh*t and weirdness around as can be seen hier and here, here and here ...

Elsewhere in the solar system we finally have Cassini close-ups of the huge Saturn storm (false-color versions here and here): more coverage and amateur pics of Dec. 25, Dec. 24 and Dec. 23; many more great views are here as is the development from Dec. 5...19. • Meanwhile the SEB revival on Jupiter continues, plus a gorgeous rotation video of Sep. 12 (from this material). • Moon & Venus on the morning of Dec. 31 from Germany and India and the constellation on Dec. 29 from Austria. • The complications of solar storm forecasting. • The coma of asteroid Sheila after its weird outburst is still there as pics from Dec. 29 (more) and Dec. 27 show - but short exposures can miss the show!

• SOHO has found its 2000th comet (more, more, more, more and mehr). • The orbit (another one) for new comet Elenin may make it bright come next fall. • Comet Hartley 2 on Dec. 29, Dec. 27 and Dec. 26. • Some reports and pictures (including a glorious composite!) from the Geminids. • A subterranean impact crater in New York. • More analysis of the 2008 TC3 meteorites here, here, here and here. • More cool pictures from the Himalayas. • Hi-res views of the ISS in front of the Moon and the Sun. • And finally some freebies: You can have 26 pages of the premiere issue of the new IOTA journal (with lots of stellar occultation conference reports), 155 pages of a kind of textbook on astrophotography and 70 pages of a Minor Planet bulletin as big PDFs, all for free. Happy new year!

An asteroid playing comet, fine Geminids and not a "solstice lunar eclipse"

2010-12-19T12:38:00.015+01:00

For 104 years the body carring the name (596) Scheila behaved like a perfect main belt asteroid - but now it's suddenly become a weird comet! This short report in German summarizes early developments and links to all that was known at the time, such as this, this and this report. Since then we have more reports from Dec. 18 (more) and Dec. 17, photo collections here, here and here and pictures of Dec. 17 (and 16 and 13; more), Dec. 16 (more), Dec. 15 (more) and Dec. 13 - it looks like the coma is fading already. • A new 'Russian' comet, C/2010 X1 (Elenin): a TV report and a Dec. 11 image. • Other recent comet pictures: 204P and 43P (both with nice tails), P/2010 V1 (earlier; not that impressive) - and Hartley 2, still a green blob amonst a lot of deep sky objects. • Organic material in the meteorites from asteroid 2010 TC3 (more and more) and 2004's comet Machholz (mehr).

The Geminids of 2010 have peaked on Dec. 14 with a ZHR a bit above 100 (just as predicted): pictures, collections and videos here, here, here, here, here, here, here, here and here. • More about that British bolide thing (with a little dashboard-cam video). • Contrary to numerous stories, the Dec. 21 total lunar eclipse (more, more, more, more) does not happen on the same (calendar) day in general as the solstice which occurs some 15 hours later: From this immediately follows that both events happen on subsequent days for 2/3 of the planet, e.g. most of Europe but also Hawaii. • Further images of the big white storm on Saturn of Dec. 14 and Dec. 13 (more) and reports of Dec. 16 and Dec. 12. • Marvellous Jupiter images (before the SEB revival) from Barbados!

A lot is happening on the Sun, though not in white light: amateur dopplergrams from Dec. 6., more and more early Dec. pics, studies of a global eruption on Aug. 1 with "sympathetic flares" (more, more), the roles of the SDO and SORCE satellites in solar studies, a storm prediction that failed, ESA's helioviewer software, and the pulsating aurora. • Finally an AGU press conference reported preliminary results on city light pollution enhancing air pollution (more, more and more) - which led to a reaction from IDA in which the study leader isn't interested, though, as he said in Q&A.

Impressive white storm appears on Saturn

2010-12-11T20:53:00.005+01:00

"Surely this must be one of the brightest and largest storms in the last few seasons," says Australian planet specialist A. Wesley about a huge white cloud that appeared on Saturn a few days ago: There are already quite a number of images showing it in the international Saturn galleries here, here and here; particularly impressive are this, this and this image. Saturn is approaching 44 Vir 3 times now, by the way, twice very closely. • The SEB revival on Jupiter continues, as again many pictures in this gallery document; there are also summary reports from Dec. 5 and Dec. 3 and some pics of Dec. 2. • A close-up of Venus from Dec. 10. • Some planetary constellations: Moon & Mercury on Dec. 8 (Oz) and Dec. 7 (US; detail), Moon crescent & Mars on Dec. 6 (very low & just after an occultation!), Moon biting the Sun on Dec. 5 (but only for the SDO), the waning lunar crescent on Dec. 4, Mercury from a plane over India on Dec. 3 and Moon, Venus, Saturn & Spica on Dec. 2.

Two major coming attractions are the total lunar eclipse on Dec. 21 (mehr, mehr) - and the Geminids on Dec. 13/14 (more, more, more and more previews): The activity profile is already picking up, we have a colorful spectrum - and there will be several rocket launches with the ECOMA particle detector to study the dust in situ; there is a campaign blog in German. • Lots of excitement in the U.K. over a bolide - that wasn't that bright at all (-5 to -7 mag. at max., I hear), just seen by many. • There may be better access to satellite fireball data for civilian researchers. • Studying an ancient impact with associated earthquake. • And a pretty weird paper linking an anecdotal story of alleged ball lightning in Oz in 2006 (one lonely witness, no physical traces!) to a fireball in the sky - which nonetheless many 'science media' picked up as something of importance, none worthy of linking here.

In other news comets 240P with a tail (also on Dec. 7), P/2010 U2 in front of M 33, P/2010 V1 on Dec. 7 and the development til now, and Hartley 2 on Dec. 7 and Nov. 27. • Also 15 years of SOHO comets, a paper on Holmes photometry with SMEI on Coriolis (alt.) and new details about a quasi-satellite of Venus. • A nice eruption on the Sun on Dec. 6 (image sequence also here -> hier -> here and stories here, here, here and here); the responsible filament also on Dec. 4 and Dec. 3. Plus a storm prediction, solar eruption studies and a paper about the January partial eclipse. • Amateurs helping Hubble with Cepheids, WW Cet, SMEI nova photometry and Eps Aur. • And night pictures from Antarctica.

Total lunar eclipse - bad for Europe, good for Americas - highlight of December

2010-12-01T23:45:00.003+01:00

Except for Venus & Saturn in the morning skies (seen in wide shots on Dec. 1 with the Moon and Nov. 26 and in detail on Nov. 28; more below) there hasn't been much - w.r.t. predictable sky events - of note lately, but that is changing in December, as previews e.g. here, hier, hier and hier show:

Dec. 1: Mercury in greatest Eastern elongation (21.5°).
Dec. 2: Venus at greatest brilliance, reaching about -4.7 (sources differ between -4.5 and -4.9) mag.
Dec. 7: Lunar crescent Moon near Mercury in the evening sky.
Dec. 13-14: Peak of the Geminid meteors - apart from the Quadrantids next January the only major shower til 2012 without much lunar interference!
Dec. 14: Mercury & Mars in conjunction, only 1° apart but very hard to observe at dusk.
Dec. 21: Total lunar eclipse with partiality from 6:33 to 10:01 and totality from 7:41 to 8:53 UTC - this is bad for Europe (and even a bit late for the Eastern U.S.). See this 3-years-old entry for general - yet still seldom-heard - advice on how to get the most out of a total lunar eclipse!
Dec. 27: Approximate beginning of a little morning visibility of Mercury.
Dec. 29: The Moon forms an 8° triangle with Saturn and Spica in the mornings skies.

Also of note are the arrival of Japan's Akatsuki in Venus orbit on Dec. 7 - and a particularly long interval between new and full Moon this month. We can also look forward to 2011 which starts right away with a partial solar eclipse on Jan. 4.

The revival of Jupiter's SEB is continuing (following the typical scenario laid out 15 years ago in Sanchez-Lavega & Gomez, Icarus 121 [1996] 1-17 almost exactly!): progress reports up to Nov. 27 and Nov. 20, an animation, a map of Nov. 29 an amateur IR image of Nov. 17 and more reports (includig big scope IR imagery) from Nov. 29, Nov. 25, Nov. 24 (also on the IR pics; more, more, more, more, more and mehr) and Nov. 22 (mentioning this blog; more). The SEB disturbance is now so obvious that it can even be detected with poor seeing (Nov. 25). • On Venus a German amateur succeeded again in November to image the planet's surface in the NIR; also UV impressions of Nov. 27.

Hartley 2 is still around: images of Dec. 1 & Nov. 27, Nov. 30, Nov. 27 (more, more), Nov. 26 and Nov. 23, plus a visual report of Nov. 30 and Herschel observations. • The origin of the Oort cloud (paper actually several months old), more thoughts about Pluto & Eris (diameters exactly the same?) and Sedna (at least as mysterious), a paper on triple Cleopatra, new NEO grants and Wisconsin (this spring) and South Africa (looong time ago) meteorite/crater stories.

In other news symbiotic variable AX Per might erupt soon, and the status of Eps Aur (plus the 7th Newsletter of Citizen Sky). • A gorgeous picture of the zodiacal light from this location at an Indian observatory deep in the Himalayas; that took some preparations! • Extremely distorted lunar images from the ISS (as predicted; p. 7), a wild Halo display and an aurora movie. • The MyDarkSky project needs support. And hi-res lunar images by amateurs here as well as here!