I noticed a large glow 25 degrees wide by 20 degrees high above the square of Pegasus just before 1 am. It was centered on the boundary between Pisces and Aquarius. I thought it might be a large dwarf galaxy but it was the Gegenschein.
More difficult to see is the Gegenschein, or opposition light. Right opposite on the ecliptic to where the sun is located, a faint elliptical glow with a diameter of about 15 to 20 degrees is visible. It is best visible at local midnight when it reaches its highest point in the sky. In December, it is lost in the bright Milky Way, so the best time to search for it is in November (in the northern hemisphere at least; from the southern hemisphere, it is May). Around 15-20 November, it is located between the Pleiades and Hyades, these two clusters providing a nice celestial landmark to the phenomenon.
