Observers on opposite sides of the world get to see events on opposite sides of the day on the 24th. Mercury is at greatest western elongation, meaning that it is best placed for observation in the pre-dawn twilight sky. Unfortunately, it will be too close to the horizon for observers in the United Kingdom and North America. However, those in the northern hemisphere can still enjoy the conjunction of Venus and Mars in the evening twilight. The pair are slowly moving apart but still appear close together. Take another look over the next few nights to see the gap between them widen.
(Click on an image to enlarge.)
Images courtesy of Mobile Observatory.
16:24 UT – Mercury reaches Greatest Western Elongation. (59% illuminated, magnitude 0.1, diameter 6.9”. Capricornus, pre-dawn sky.)
The constellation Leo Minor (the Little Lion) culminates at midnight tonight. (All night.)
The waxing crescent Moon appears close to M45, the Pleiades open star cluster. (Taurus, evening sky.)
Learn more about every upcoming astronomical event in 2015 An Astronomical Year (Kindle eBook) and The Astronomical Almanac (2015-2019) (Kindle eBook) and The Astronomical Almanac (2015-2019) (Paperback Edition).
The Amateur Astronomer’s Notebook allows astronomers to log 150 observing sessions and includes an appendix of hundreds of suggested deep sky objects.