For the third celestial object in our series, let’s talk about dippers, both big and small. They figured into the conversation about both Polaris and the Draco constellation, and they are one of the most commonly known and easily found of all the star patterns.
The dippers circle around Polaris, making a full rotation every 23 hours and 56 minutes. For those in the northern hemisphere the Little Dipper is always above the horizon throughout the year, but the Big Dipper’s visibility is dependent on the time of the year. In the spring and summer it is high in the sky, and then in autumn and winter it is low to the horizon and even below the horizon for those below about 35 degrees north. The closest star in the Big Dipper is Megrez at 63 light years away from Earth, and the furthest is Alkaid at 210 light years.
The Big and Little Dippers are actually something known as an asterism, a star pattern that is not a constellation. The Big Dipper is actually part of a larger group of stars known as Ursa Major, or the Great Bear and the Big Dipper is the tail and hindquarters of the Bear. The Little Dipper’s stars are also part of constellation, the one known as Ursa Minor or the Little Bear.
Ursa Major and Ursa Minor were both listed in Ptolomy’s constellations in 270 AD and their mythology dates back to antiquity and across a wide universe of cultures. I am fond on the Roman version, were Juno, the wife of Jupiter and the king of the gods, eliminated a rival for Jupiter’s affections by turning the nymph Callisto and her son Arcas into a bear and bear cub. To protect them from Juno, Jupiter then put them in the sky. The Mik’Maw of Canada and Iriquois nations look at the Ursa Major as a bear without the tail and think of the three stars in the handle of the Big Dipper (Alkaid, Mizar and Alioth) as hunters who are chasing the bear.
The big dipper shows up on the state flag of Alaska, the coat of arms and flag of Madrid, and were painted by van Gogh. Third Eye Blind fans might own their fourth album named after Ursa Major.