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M82

Messier 82
Cigar Galaxy
Peculiar Galaxy
Right Ascension 9h 55m 50s Best Seen 1/1-12/15
Declination 69° 40' 49" Magnitude 8.8
Constellation Ursa Major

Actual		 Compared
to Milky Way
Distance 12 million ly --
Actual Brightness -- --
Diameter 16 thousand ly 0.16
Mass 50 billion suns --
Galactic Type Ir-II Sbc

What To Look For Through The Telescope

  1. Recommended eyepiece: 80mm

  2. When people look through the telescope they should see a cigar-shaped fuzzy patch of light.

  3. If they are having trouble seeing it, have them look at a star near the edge of the field, then look back to the center out of the corner of their eye.

  4. The view through the telescope will not look like photographs they may have seen. A photograph of a galaxy may have an exposure of many hours. This long exposure brings out the spiral arms and other details. Our eyes allow the light to collect for only about 1/30 of a second before they refresh themselves and start over again.

M82 Information

  1. This galaxy is also called the “Cigar Galaxy” because it’s shaped like a cigar.

  2. Johann Bode discovered this galaxy and its neighbor, M81, on December 31, 1774. Pierre Méchain independently rediscovered the two galaxies in 1779, and reported them to his friend Charles Messier. Messier included them in his famous catalog after he measured their positions on February 9, 1781. (M81 is a spiral galaxy.)

  3. Recently in this galaxy’s history – a few tens of millions of years ago – a close encounter occurred between M81 and M82. As a result, M82 is a “starburst galaxy.” Due to the close encounter, shock waves were sent through M82, triggering an intense period of star formation.

  4. Along with new stars forming, lots of gas is flowing and being pushed around, making this galaxy a strong source of radio emission.
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References
Item Updated Notes
Coordinates 2003-01-15 tweaked with SIMBAD and SEDs site
Distance 2003-01-15 previous: 6.5 million ly
– BUT wrong, see http://www.seds.org/messier/m/m082.html
Actual Brightness --
Diameter 2003-01-15 OK with U of Leicester Physics and Astr.
http://www.star.le.ac.uk/astrosoc/whatsup/galaxies.html
another site says 55,000 ly
http://www.astrosurf.com/jwisn/m82.htm
Mass 2003-01-15 have found no support, but looks OK
Galactic Type 2003-01-15 previous: Pec – BUT SEDs says Ir-II
Other Information 2003-01-15 info from SEDs site
previous: “Evidence suggests that a violent explosion occured in the central regions of the galaxy about 1.5 million years ago. This explosion would have involved several million stars.” – I think this means the starburst activity now described