M81 (NGC 3031)

      M81 is one binocular field east of sigma UMa. This is an exceptionally fine spiral galaxy, one of the most celebrated in the heavens. It's one of the most dense known with a mass of 250 billion Suns. With an apparent visual magnitude of 6.9, large binoculars give a splendid view of its core, populated by red giants. A medium telescope puts details in the spiral arms. It's about four and a half million light years away.
      M82 is much smaller, much less-well defined compared to its larger neighbour—it's about a half-degree to the north of M81. With an apparent visual magnitude 8.4 it's easily seen in large binoculars, which however fail to give much detail.
      A medium-sized telescope brings in dark dust lanes surrounding an odd-shaped core. Stars are forming here at a high rate, as the two galaxies exchange material. This galaxy has a smallish black hole, with a mass of about 500 Suns.

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