Explanation:
If you look carefully enough, you can even see the glow of the
Sun in the opposite direction.
At night this glow is known as
the gegenschein (German for "counter glow"),
and can be seen as a faint glow in an extremely dark sky.
The gegenschein is sunlight back-scattered off small interplanetary
dust particles.
These dust particles are millimeter sized splinters from
asteroids and orbit in the
ecliptic plane of the planets.
Pictured above, the gegenschein is seen superposed toward the constellation of Pisces.
The gegenschein
is distinguished from zodiacal light by the
high angle of reflection.
During the day, a phenomenon similar to
the gegenschien called the glory can
be seen in reflecting air or clouds opposite the Sun from an airplane.
APOD Editor to Discuss "Best of APOD 2006" Pictures in NYC on January 5