The elusive little planet Mercury has begun its apparition as an evening star following its superior conjunction behind the Sun on 2009 JUL 13. This should be a fine apparition for observers in the southern hemisphere, but a challenge for those of us in the north.
I’ve created two graphics illustrating Mercury’s evening apparition as viewed from Chicagoland and Sydney. They should well serve observers in the two respective hemispheres. They can be seen at: http://www.curtrenz.com/astronomical
All dates given here are based on CST. Mercury will reach its greatest altitude at 30 minutes after sunset from Chicagoland on AUG 11 at 4.7°. It will achieve its greatest eastern elongation of 27.4° from the Sun on AUG 24. The planet will achieve dichotomy (50% illuminated like a Half Moon) on AUG 25. Before that date it will appear gibbous and afterward a crescent. While decreasing in brightness, it will then fall to inferior conjunction between Earth and Sun on SEP 20.
Mercury will appear to pass 0.6° north of the first magnitude star Regulus on AUG 02. The waxing crescent Moon will pass 3° south of Mercury on JUL 22 and again on AUG 22.
Photos and descriptions of Mercury during the current evening apparition would be welcome additions to this thread.