Andromeda



Description and General Notes

Andromeda is sometimes called the Chained Maiden, and is one of several constellations linked by the Greek myth of Perseus. According to the story, Andromeda's mother Cassiopeia boasted of her beauty, claiming she was more beautiful than the Nereids, daughters of the sea Titan Nereus and companions of the sea god Poseidon, Poseidon sent a sea monster named Cetus to ravage the coast. Andromeda's father Cepheus consulted an Oracle and was told that he must sacrifice his daughter Andromeda to the monster to save the land. And so, in time, Andromeda was chained to a rock by the shore, to wait for the monster and her doom. The hero Perseus, fresh from slaughtering the Gorgon Medusa, killed Cetus and rescued Andromeda. Claiming her as his reward, he married her, though she had been betrothed to Phineas (conspicuous by his absence to this point). Phineas challenged Perseus at the wedding, but was turned to stone when Perseus pulled Medusa's head out of a sack.

Andromeda is best viewed in mid-to-late fall, and through the winter season. By spring and summer it is washed out by daylight at best. For southern hemisphere viewers it is increasingly more difficult to see as you move south.


[Image generated by Starry Night 4.52]

Globular clusters

Planetary nebulae

The Blue Snowball (23h 25.9m; 42° 33’) is a little puffball of gas surrounding a central star in the constellation of Andromeda. In the New General Catalog it’s number 7662, so a short designation is NGC7662. It’s also C22 in Patrick Moore’s Caldwell catalog. You would never mistake this for a comet so it didn’t appear in Messier’s catalog (if he even saw it) and it looks distinctly star-like in a small telescope (say, 60-125 mm), except for the intense blue colour, which is quite startling to see when you come across it in a sweep of the sky. In a larger scope at about 200x the nebular character is more obvious, though you still might mistake it for a planet due to its spherical appearance and small size. The image below was captured with a 110 mm f/6.5 scope and a 20D camera, and is cropped, but not reduced, from the full frame:



Galaxies

M31 — the Great Galaxy in Andromeda. (0h 42.7m; 41° 16’) This is an obvious object in reasonably dark skies, but I am always disappointed when trying to view it in the city. Expectations are always high because published images are spectacular, but in city skies and the naked eye, even M31 fades into the background. Under a dark(er) sky and with a small telescope or a pair of binoculars it is well worth a long look to view the nebulosity around the fuzzy core Looking slightly away from the core may bring out further details due to the phenomenon of averted vision. In some ways, larger ‘scopes or high powers will not do the galaxy justice: M31 is about 3 degrees across, and simply won’t fit into the field of view at high powers. However, even though the entire galaxy will not fit in the field, it is bright enough that with a large scope you can cruise around the core, especially when using averted vision to pick up details which are simply not visible in smaller scopes.

Double Stars

Variable Stars

R Andromedae (0h 24.0m; 38° 35’) this has a wide range in brightness, from magnitude 5.8 to down to 14.9 and back over a timeframe of 409.33 days, so tracking this star’s brightness is a long-term project.

More to come...