M81 and M82

M81 and M82

Spiral Galaxies
NGC 3031 & 3034
Ursa Major
9H 55.6m +69° 04'

Separation: 38'
Distance: 12 million light-years

Requires intermediate skills

Skill Level
Both M81 and M82 are bright, but you will need a small focal length or a mosaic to capture both in the same frame.

MarchBest Month
March is its best month to capture this pair.


Recommended Equipment
The best telescope to capture both galaxies in the same field is probably a small refractor.

With more effort you can create a mosaic of the entire region using a widefield Newtonian.


Image Stats
Meade 8" SN LXD75
Various cameras

Composite of M81 image, M82 image, and mosaic of images for background.

See Also

This beautiful pair of galaxies was discovered by professional astronomer Johann Bode in 1774, more than a hundred years after the invention of good quality telescopes. Today, anyone with a modest telescope can easily see the fuzzy patches of light from these two galaxies. So why did it take a hundred years for them to be discovered? As with so many things in life, it's easy to find something if you know where to look. In 1774, before telescope go-to computers, before "Sky Atlas 2000.0" and even before "Astronomy for Dummies," finding a deep sky object was strictly trial and error.

Today, M81 (the large oval galaxy at lower-left) and M82 (the strange galaxy at upper-right) are two of the easiest galaxies to find and photograph.

M81 and M82 are more than 12 million light-years away, and are separated from each other by about 100,000 light-years. There is clearly something wrong with M82. Many astronomers believe that a close encounter with its partner caused M82 to erupt in a frenzy of star formation and destruction.

See also this close up of M81 and close up of M82.


I begin all astrophotography sessions by printing out a chart of the region that I'm going to photograph. Next I orient myself by determining how the telescope moves within the chart. For example, if pressing the North button on the telescope moves stars diagonally towards the lower-left, then I know that North on the screen is to the upper-right. This is enough to figure out which way to hold the chart to match the camera output.

When capturing a mosaic, I use the chart to plot where I've taken each shot. This insures that I capture enough images to cover the whole region and that I provide enough overlap between shots. For example, below is the chart that I used to capture the M81 and M82 widefield image. Each box is one image.

Chart for mosaic of M81 and M82