From NASA's Astronomy Picture of the Day
The spiral galaxy spans about 100 thousand light-years and is
seen almost exactly edge-on from our perspective.
In
fact, about 30 million light-years distant in the constellation Andromeda, NGC 891 looks a lot like our Milky Way.
Credit: Composite Image Data - Subaru
Telescope (NAOJ), Hubble Legacy
Archive, Michael Joner, David Laney (West Mountain Observatory, BYU); Processing - Robert
Gendler
At
first glance, it has a flat, thin, galactic disk and a central bulge cut along the middle by regions
of dark obscuring dust.
The
combined image data also reveals the galaxy's young blue star clusters and
telltale pinkish star forming regions.
And
remarkably apparent in NGC 891's edge-on presentation are filaments of dust that extend hundreds of
light-years above and below the center line.
The
dust has likely been blown out of the disk by supernova explosions or intense
star formation activity.
Faint
neighboring galaxies can also been seen near this galaxy's disk.