Wednesday, September 30, 2009

The eclipse of Epsilon Aurigae has begun: 0.3 mag. drop evident

Go to the light curve generator of the AAVSO, enter "eps aur" as the object, 60 or 80 days as the interval and select only "V" magnitudes: out comes a light curve that monotonously falls from a level 3.0 mag. to 3.25 mag. right now over approximately the past month (using "visual" instead leaves a much noisier picture). Thus the long-awaited eclipse of mystery star Epsilon Aurigae has clearly begun, the first in 27 years - and this time the interest is higher than ever, esp. with the (much promoted) Citizen Sky campaign under way. Here the lightcurve is discussed in detail (earlier, still earlier, even earlier); using the last eclipse of the weird long-period system as a template, the brightness should drop to 3.8 mag. over the next two to three months and then hover there throughout 2010. • Meanwhile an outburst of Z And has been reported.

In other news there were two sunspot groups on the disk simultaneously, something not seen in a long time! A close-up of one of the groups on Sep. 26 (when also a big prominence was seen) and reports from Sep. 23 (more), Sep. 22 and Sep. 21. • Sun-related also a comparision of H-alpha telescopes (but is it fair?) and new insights about the solar cycle and a current surge of cosmic rays due to the low activity level (more, more and more). • In the comet world we have the first discovery by the La Sagra Sky Survey, comet 217P over M 42 (also an AAPOD) and one day later, Garradd with a long tail (by F. Kugel), the case of Pigott-LINEAR-Kowalski and Christensen. • Big bolides have been reported e.g. from Argentina, Canada and Namibia, numerous new weak meteor showers have been recognized; we have a new PHA - and the discoverer of 2008 TC3 has now a piece of "his" asteroid after it turned into a meteorite shower over Sudan! There will be a conference on the subject right there, in December - including further meteorite searching!

• Here is a long report about a possible detection of Io's atmosphere by an amateur during a mutual event; also "normal" event reports of Sep. 26 (also as a dramatic video!) and Sep. 9. Plus fine Jupiter images from September and also July - the latter taken at Pic du Midi with 1 meter. • There's now another Galaxy Zoom concentrating on the center region (also reported here) - plus a direct comparision of the two full-sky mosaics discussed 2 weeks ago: Mellinger's has higher resolution becuase Brunier's is actually oversampled. (There's also a another mosaic of only the Lagoon Nebula.) • A short-lived rocket experiment created a glowing cloud in the U.S. sky, causing some news coverage (see also here, here and here). • Also a remarkable amateur picture of the HTV (see also here and here) - and amateur satellite watchers found out what a secret satellite is probably good for. • Sky highlights in October 2009 mostly deal with constellations of the planets.
  • Oct. 6 morning: Largest elongation of Mercury with 18° (best morning apparition of the year for the Northern hemisphere; best view should be from Oct. 6 to 15)

  • Oct. 8 morning: Mercury just 0.3° SW of Saturn (which just emerges from the Sun's glare); Mercury 5 times brighter.

  • Oct. 10 morning: Venus, Saturn and Mercury close together

  • Oct. 12 morning: Moon close to Mars

  • Oct. 13 morning: Venus 0.6° W of Saturn (and 100 times brighter) - and the opposition loop of Jupiter ends

  • Oct. 16 morning: Mars, Saturn, Venus, Mercury and the Moon form a nice constellation

  • Oct. 21 late afternoon: The Moon occults Antares for Europe
Meteor-wise it'll be mainly the Orionids that should cause interest - and around their Oct.21 peak the Moon is practically gone. • Finally a report from the HHT, a star party in Eastern Germany (another, another and another report); also a note on a starparty on Palomar Mtn. - and the 1st issue of Practical Astronomy is out.

1 comment:

Anonymous said...

Hi Daniel,

Thank you for encouraging me with the fledgling astronomy magazine.

All the best,