Explanation:
Big, beautiful spiral galaxy
NGC 7331
is often touted as an analog to our own
Milky Way.
About 50 million light-years distant in the northern constellation
Pegasus,
NGC 7331 was recognized early on as
a spiral
nebula and is actually one of the brighter
galaxies
not included in Charles Messier's
famous
18th century catalog.
Since the galaxy's disk
is inclined to our line-of-sight, long
telescopic exposures often result in an image that evokes a strong
sense of depth.
The effect is further enhanced
in
this sharp image
by galaxies that lie beyond the gorgeous
island universe.
The background galaxies are about one tenth the
apparent size
of NGC 7331 and so lie roughly ten times farther away.
Their close alignment on the sky with NGC 7331
occurs just by chance.
Seen here through faint foreground dust clouds lingering above the plane of
Milky Way, this visual grouping of galaxies is
also
known as the
Deer Lick Group.
Tonight:
Perseid
Meteors by Moonlight