Who's got the best mega-mosaic of the whole sky in visible light?

What an amazing coincidence: Practically simultaneously two color mosaics of the whole sky with more than half a billion pixels each have been published, one by a physicist, the other by a science writer, but both did their work as tireless amateur astronomers over many months. One is by Axel Mellinger who also describes his work in a scientific paper: Great care was taken to achieve photometric calibration and foreground subtraction. This amazing achievement went unnoticed in an ESO Press Release a few weeks later presenting another mosaic by Serge Brunier which has even more pixels but less photometric precision it would seem (the images were taken with a DSLR cameras and stitched with commercial software). Still ESO is incorporating the latter mosaic into its "Giga-Galaxy Zoom" project - let's see which mosaic will become the new gold standard (as Mellinger's original mosaic made from chemical pictures in 2000 might be called).

In other news we have a rare outburst of the suspected UGWZ star VX For (a sensation for some), the 125th supernova discovery by an individual amateur, the Catalina Real-Time Transient Survey (where everyone can help) and the Hyper-Velocity Stars Project utilizing the SDSS Galaxy-Zoo-style. • From the 22 July Total Solar Eclipse we have a hi-res corona composite and a 3rd contact by Druckmüller & al., the official word and a 21-min. video about the Indian commercial eclipse flight, pictures and a slide show from Wuhan, a report from Hangzhou, a narrated slide-show from Wuzhen (featuring yours truly; incl. Wuhan) and a report from Shanghai. There are also a very detailled report on the 1 Aug. 2008 TSE, a speculative "eclipsology" blog - and, vastly more on the fringe, the TSE/UFO madness of 2009 ... • Talking about the Sun, there are speculations about its fading B field (summarized here and discussed here) and facts about the - minuscule - climate impact of solar events. And it was 150 years ago that the most powerful flare ever struck.

• Many more mutual events of Jovian moons have been observed, e.g. on Sep. 12, Sep. 8/9 (more), Sep. 1, Aug. 24/25 (more, more), Aug. 19 (more), Aug. 15 and other dates. • Pictures of the Wesley impact spot on Aug. 18 and various dates; it's pretty much gone now. • There is yet another comet McNaught with a moderately promising outlook; we had unusual activity in 217P (earlier, more), the recovery of P/2003 A1 (LINEAR), a new Hill, the unusual asteroid 2009 QY6, indications on 17P/Holmes splintering in connection with its 2007 outburst, the 2009 Wilson Awards and the 50th comet discovery by R. McNaught. • There were lots of reports about an Irish bolide on Sep. 3 while more has been reported about the Belgian case - and fine composite images of the 2009 Perseids have been published. • A fine "Etruscan Vase" Moon (more here), other recent "Vases" of Sun & Moon and various atmospherical optics in Ireland, plus a visit to Tacande Obs. on La Palma. • Finally some highlights of September 2009 -

• Sep. 16: Uranus in Opposition at 5.7 mag. (try it with the naked eye).
  
  
• Sep. 17: Saturn in Conjunction with the Sun, spoiling attempts to follow the ring plane crossing events from Earth.
  
  
• Sep. 29: The Moon visits Jupiter, still a great sight (and the main target of the Galilean Nights a month later).

While the planet Mercury is in conjunction with the Sun this month, it can still be "observed" very well near the end of it, by the way: MESSENGER will perform its 3rd close fly-by on Sep. 29 (about when a morning apparition begins) for a final gravity assist that will enable it to enter orbit about Mercury in 2011. With more than 90 percent of the planet’s surface imaged during the previous two fly-bys, the team will turn its instruments on specific features and uncover more information about the planet closest to the Sun.