Explanation:
As far as ghosts go,
Mirach's Ghost isn't really that
scary.
In fact,
Mirach's Ghost is just a faint,
fuzzy galaxy, well known to astronomers,
that happens to be seen nearly along the line-of-sight to
Mirach,
a bright star.
Centered in
this star
field, Mirach is also called Beta
Andromedae.
About 200 light-years distant,
Mirach is a red
giant star, cooler than the Sun but
much larger and so intrinsically much brighter than our
parent star.
In most telescopic views, glare and
diffraction
spikes tend to hide things that lie near Mirach and make the
faint, fuzzy galaxy
look like a ghostly internal reflection of the almost
overwhelming starlight.
Still, appearing
in this sharp image just above
and to the right of Mirach, Mirach's Ghost is cataloged as
galaxy NGC 404
and is estimated
to be some 10 million light-years away.
