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For those unfamiliar with astrophotography, there are a few neat things to note about this image. Most of the larger points of light that have what looks like a
by Rooster61 12y ago
For those unfamiliar with astrophotography, there are a few neat things to note about this image. Most of the larger points of light that have what looks like a cross going through them are actually stars in our own galaxy between the Earth and Andromeda.
The crosses, or spokes, through each of the stars is caused by the struts holding Hubble's secondary mirror in place above the primary mirror. Every poinpoint of light in this picture actually has these spokes, but they are only really visible on the biggest, brightest spots.
This is also visible in Hubble's Deep Field photos as there are numerous local stars in the foreground.
The reddish, fuzzy, oblong objects that are a bit bigger are other galaxies far past Andromeda. Most appear red because of a side effect on light traversing such a long distance before reaching us called redshift.