big-dipper-web.jpg

This is a photo I took of the big dipper. More photos are here.

Here is a practice drawing from Starry Night.

Here is Van Gogh’s impression of the Big Dipper. One of the first asterisms many people learn to recognize is the seven-star Big Dipper, consisting of the seven brightest stars of Ursa Major, the great bear. These stars are, starting with the end of the dipper’s handle (or end of the bear’s tail), Alkaid, Mizar (with its fainter optical companion Alcor), Alioth, and then clockwise around the bowl starting with where the handle joins it, Megrez, Phecda, Merak, and Dubhe. In addition to the Big Dipper asterism are less-familiar portions of the bear. Three medium-bright stars form the bear’s nose, and a pair of triangles of stars and a third very skewed triangle (nine total) form three visible paws. The bowl of the dipper looks like a saddle on the bear’s back. Here is a map of Ursa Major.

Nearby constellations

The bear seems to be chased by Canes Venatici (hunting dogs–directly below Alkaid if viewing the dipper so the bowl faces up–see the bright star bottom center of the photo at the beginning of the post). It seems to be walking on the little lion, Leo Minor. It is sniffing out the hard-to-see lynx. The dragon (Draco) winds between the big and little dippers. Bootes the herdsman seems to be chasing the bear away.

Galaxies

Ursa Major is home to many galaxies, it being well outside the galactic plane (visible as the Milky Way) so one has a clear view out of our galaxy. M81 (Bode’s Galaxy) is one of the brighter galaxies in the sky, just visible to the naked eye under very good conditions. It is next to M82, the Cigar Galaxy, and in fact, the two recently had a close encounter that disrupted both galaxies. In addition, M101 (Pinwheel Galaxy) is near Alkaid (so is the Whirlpool Galaxy, M51, though technically, it is in Canes Venatici). Other galaxies in or near Ursa Major include M97, M108, M109, and nearby M63, M94, and M106 in Canes Venatici.

History and Mythology

Ursa Major may be one of the oldest constellations. American Indians, Australian Aborigines, and ancient Romans all saw it as a bear, and the three cultures had not interacted for thousands of years. It may be 50,000 years old even (to a time when humans worshiped bears). See AAVSO’s notes on the subject.

In any case, the Greek myth was that Zeus fell in love with Callisto. Zeus’s jealous wife turned Callisto into a bear (Ursa Major) out of revenge. Later, Arcas, Callisto’s son by Zeus, nearly killed her in a hunt (unknowingly) but Zeus intervened by turning Arcas into a bear (Ursa Minor) and placed them both in the sky.

See Wikipedia’s article for more information.