2011-06-28

M 81




Photo by Pittendreigh

REMARKS: M81 was discovered by J.E.Bode in 1774, and it is sometimes referred to as Bode's Nebula. This is a spiral galaxy tilted at about 32 degrees from being edge-on.

M82 is the brightest and best known of the irregularly shaped galaxies. Because of photographic evidence and the fact that M82 is a strong radio source, many have believed that the galaxy was exploding. The galaxy is certainly in turmoil of some sort. What may have happened is a close passage with M81 some 200 million years ago. The gravitational tidal effects disturbed stellar orbits. Gas clouds were effected, colliding, and creating new stars. Some mass may have been thrown outward.




HOW TO FIND IT:

Draw an imaginary line from Gamma Ursae Majoris to Alpha Ursae Majoris. Continue that imaginary line an equal distance beyond Alpha.

WHAT TO LOOK FOR:

First, be aware that M81 and M82 are close neighbors, but you will be able to distinguish which is which.

When looking at M81, look for an diffused oval shape. You should be able to see the bright nucleus of the galaxy. What you might not see are the spiral's arms. You might need a telescope the size of an 8 inch reflector to see these arms, but some can see hints with smaller telescopes. Look for a string of faint stars around the diffuse area, or a halo.

M82 will be a cigar shaped object in the sky, not far from M81. It will not be as bright as M82. It will have an irregularity of brightness, but without the granular texture of M81.



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