This article was contributed by David Baumgartner as part of a local series on astronomy.
The Big Dipper is no doubt the best-known constellation in the sky, even more so than Orion or Pleiades. I’m sure there are many people who know just one group of stars, and that is always the Big Dipper. This is how all the amateur astronomers find the North Pole star, by first finding the Big Dipper and the two bright stars in the bowl that point almost directly to Polaris.
This group of stars has many names around the world. In England it is called the Plough. Other people call it Charles’ Wain, or the Churl’s Wain. (Wain is a wagon; churl is a peasant.) But the official name used is the Great Bear. In Latin it is Ursa Major. This is somewhat odd because a bear is one thing it does not look like.
But the Big Dipper is only part of Ursa Major. There is a large area to the right and below which also belongs to this constellation. If you try to draw a bear out of this group of stars the Dipper is his back and tail. I have never seen a bear with a tail so long as portrayed on the sky maps. But the shape does look like a dipper. That must be why in modern times it is known as the Big Dipper.
The Big Dipper is good to use as an eye test. Take a look at the bend in the handle. If you have good eyesight you can see Mizar and its little companion Alcor. But it would take a telescope to split Mizar itself into a double star only 1/50th as far apart as Mizar and Alcor.
Spring is here, and that means better clearer nights for gazing at the heavens. Don’t forget to check out the Lyrid meteor shower which peaks on April 22. My wish is that everyone would have the chance to enjoy astronomy as much as I do. It is a great way to enjoy time, whether you are alone, or with your friends. Clear skies.
Sky Watch
April 22: Lyrid meteor shower peaks and New Moon
April 27: Moon passes 6° south of Venus
Apr 30: First Quarter Moon