These two galaxies can be seen in the constellation Ursa Major near the asterism "The Big Dipper."
They are interacting through mutual gravatational force and have done so for the past billion years.

They come close about every 100 million years, causing distortions in each galaxy. That effect can be seen in the open spiral arms of the galaxy on the left, M81, and in the red areas of the galaxy on the right, M82. M82 is seen edge on (like looking at the side of a Frisbee) while M81 has more of an open face to us. They are separated by about 150,000 light years. (Apod/Nasa.gov)

They will eventually merge into a single galaxy in about a billion years. M81 is about 70,000 light years in width, making it 70% the size of our Milky Way galaxy. They are 12 million light years from us.
The circular blue area just above M81 is a dwarf irregular galaxy that is a companion to M81. It is designated as UGC 5336 (HolmbergIX) and is very young at about 200 million years in age. Speculation is that it was formed during the last one or two times M81 and M82 passed close. It would have been formed when the interacting tidal forces between M81 and M82 ripped stars loose
from one or both galaxies. (medusa.as.arizona.edu)

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Dates Taken:
March 10, April 4,5 and 6, 2008
Locations:
March 10: Ray Roberts State Park, TX
April 4, 5 and 6: Ft. Griffin State Park, TX
Telescope:
Takahashi TSA-102 f/8
Mount:
Takahashi EM-10 Temma 2, guided by in-camera guide chip
Camera:
SBIG ST-8XME NABG w/ CFW-9, Astrodon LRGB
Exposures:
Lum 300 min, binned 1X1; Red 90 min; Green 80 min; Blue 100 min; all color binned 2X2
Total LRGB: 9.5 hours
Processing:
CCDStack and Photoshop CS