~ St. Maarten’s Backyard Astronomy for November 25 & 26 ~
Sun rises at 6:23am
Sun sets at 5:34pm
Moon phase: First Quarter Moon
Moon sets at 10:30pm Saturday
Moon rises at 12:37pm Sunday
Last weekend, we suggested you take a glance at the winter circle, giving special attention to Orion the Hunter. Orion is currently rising on the eastern horizon in the mid-evening. From late November through the winter, people often notice Orion in the evening sky, and many enjoy teaching this constellation to their children. You can observe this constellation and watch it for months to come.
Orion is perhaps the easiest-to-identify of all constellations due to the pattern called Orion’s Belt: three medium-bright stars in a short, straight row. As seen from mid-northern latitudes, Orion appears to be lying on his side – with his Belt stars pointing upward. Orion’s two brightest stars – Betelgeuse and Rigel – shine on opposite sides of the Belt.
As night passes, the Earth spins beneath the sky, causing Orion to arc across our sky. Like all the stars, Orion’s stars rise some four minutes earlier with each passing day, or about two hours earlier with each passing month. This shift in Orion’s location is due to Earth’s movement in orbit around the sun. As we move around the sun, our perspective on the stars surrounding us shifts. At the same hour daily, all the stars in the eastern half of sky climb up a bit higher, whereas all the stars in the western half of sky sink a bit closer to the western horizon.
From Orion, it’s easy to “star-hop” over to the asterism known as the Pleiades or M45. Imagine a straight line through the three stars of Orion’s Belt to the right – and you come to a V-shaped pattern of stars with a bright star in its midst. The V-shaped pattern is the Face of Taurus the Bull. The bright star in the V – called Aldebaran – depicts the Bull’s Eye. A bit past Aldebaran, you’ll see the Pleiades cluster, which marks the Bull’s Shoulder.
You can view the Pleiades with either the unaided eye or an optical aid. There is something very recognizable about this particular star pattern in the sky: it’s tiny and misty, but if you squint and stare, you will notice that its six brightest stars like a little dipper. Once you learn to see it, you can pick it out with confidence.
Historically, the Pleiades star cluster has served as a calendar for many civilizations. The Greek word “Pleiades” means “to sail.” In the ancient Mediterranean world, the day that the Pleaides cluster first appeared in the morning sky before sunrise announced the opening of the navigation season.
The modern-day festival of Halloween originates from an old Druid rite that coincided with the midnight culmination of the Pleiades cluster. It was believed that the veil dividing the living from the dead is at its thinnest when the Pleaides culminates or reaches its highest point in the sky – at midnight.
The Pleiades is sometimes called the Seven Sisters. But if you look with your eye alone, it’s likely you’ll only see six stars in the Pleiades. Some old Greek legends explore what might have happened to the missing sister, sometimes called the Lost Pleiad.
People with exceptional eyesight have been known to see many more stars in the Pleiades cluster. Claims go up as high as 20 stars. Maestlin, the tutor of Johannes Kepler, mapped out 11 Pleiades stars before the invention of the telescope.
However, you must be willing to spend time under a dark, moonless sky to see more than six or seven Pleaides stars. It’s been said that eyes dark-adapted for 30 minutes are six times more sensitive to light than eyes dark-adapted for only 15 minutes. The surest way to see additional Pleiades stars is to look at this cluster through binoculars or a telescope.
In both myth and science, the stars in the Pleiades are considered to be sibling stars. Modern astronomers say the Pleiades stars were born from the same cloud of gas and dust some 100 million years ago. This gravitationally bound cluster of several hundred stars looms about 430 light years away, and these sibling stars drift through space together at about 25 miles per second. Many of these Pleiades stars shine hundreds of times more brightly than does our own sun.
Thank you for keeping up with the Night Sky articles. If you are out later on in the week, each star rises about four minutes earlier each day than written here, and the moon rises 50 minutes later. Night Sky is researched and compiled by Lisa Davis-Burnett. Earthsky.org is a key resource for information and images. Questions or comments? Email This email address is being protected from spambots. You need JavaScript enabled to view it.
