Explanation:
The mysterious blue reflection nebula found in catalogs as VdB 152
or Ced 201 really is very faint.
It lies at the tip of the long
dark nebula Barnard 175 in a
dusty complex that has also been called
Wolf's Cave.
The cosmic apparitions are
nearly 1,400 light-years away along the northern Milky Way
in the royal constellation Cepheus.
Near the edge of a large molecular cloud,
pockets of interstellar dust in the region block light from
background stars or scatter light from the embedded bright star
giving the
the nebula
its characteristic blue color.
Ultraviolet light from the star is also thought
to cause a dim reddish luminescence
in the nebular dust.
Though stars do form in
molecular clouds, this star
seems to have only accidentally wandered
into the area, as its measured velocity through
space is very different from the cloud's velocity.
This deep telescopic image
of the region spans about 7 light-years.
Poll:
Which of October's APODs should be the APOM?
