Dwarf spiral galaxy in Draco

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Star-hop chart

During the summer months, NGC 6503 is high overhead in the northern sky. This galaxy is about 4 arcminutes west of an 8th magniude star, which can help in locating it. It is called a "dwarf spiral" because it is relatively small for a spiral galaxy, with a diameter of 30,000 light years, less than 1/3 the size our own Milky Way galaxy.

At magnitude 10.2, NGC 6503 appears fairly bright for a galaxy, and at an estimated distance of about 17 million light years, it is one of the closer galaxies to Earth. It can be seen in even small telescopes. Visually, it has an obvious elongated shape. Through my 18-inch telescope, the interior of the galaxy has a mottled texture, and its edges have an irregular outline. The diameter of this galaxy is about 35,000 light years, which is about 1/3 the diameter of our own Milky Way Galaxy.

Image details:  Exposure times of 45 minutes luminance, and 24 minutes each of red, green, and blue, taken with an SBIG ST-8300M imager and a 14" Meade LX850 telescope at f/8.

August 2017