Mercury at Greatest Eastern Elongation

December 11 – Mercury at Greatest Eastern Elongation. The planet Mercury reaches greatest eastern elongation of 20.8 degrees from the Sun. This is the best time to view Mercury since it will be at its highest point above the horizon in the evening sky. Look for the planet low in the western sky just after sunset.

Source: http://www.seasky.org/astronomy/astronomy-calendar-2016.html