One of the more interesting galaxies in the night sky, M51 or the Whirlpool Galaxy is actually two galaxies. M51 itself, sometimes denoted M51a, is the primary galaxy, a beautiful full spiral galaxy with elongated arms and visible tidal streams. The galaxies arms are threaded down the centers by intricate and complex weaves of infrared-emitting dust and hydrogen nebula, which in this image gives them a rusty red appearance.
Adjacent and apparently interacting with M51 is it’s companion, the much colder and redder M51b, also called NGC 5195. This smaller companion is more distant than M51a, but still in proximity. It exhibits some of it’s own tidal streams, in the form of fingers flaring off away from M51a, and a longer yellowish tail from the upper right. The proximity and location of M51b give us a unique look at the dust structure in one of M51’s arms that partially obscure the smaller galaxy.
Within this same region of the night sky, which happens to be in the constellation Canes Venatici (the Hunting Dogs), which is near the Big Dipper, a number of other more distant galaxies can be seen. The whole region is scattered with galaxies as you can see in the image below, which is a crop of the region slightly above and to the right of M51.
Below M51, near the star , a significantly more distant cluster of galaxies can be seen:
This cluster, just below the star HIP66004, is over two billion light years away. It is one of the most distant objects a simple telescope such as my own can see, and barely see it does. This cluster has no useful name other than a long, cryptic computer generated one from some automated catalog. This is the most distant object I have thus far managed to image myself as well.