what's up in the sky, February, 2011
Post date: Jan 25, 2011 7:30:55 PM
The Pleiades is a cluster of stars that appear in literature and myths of people and cultures around the globe. They are mentioned by Homer in the Iliad and Odyssey, the Bible Job 9:9 and 38:31, and it has been suggested they are the Star of Najm mentioned in the Quran. They became a logo for Fuji Heavy Industries in 1953 when six Japanese companies merged to become the transportation conglomerate FHI. We see it on the automobiles they build, the Subaru. The satellite company Thuraya is named for the Arabic word Pleiades. They are also on the city flag of Durham, North Carolina. Even Messier,known for his list of objects that weren't comets, put them on his list as M45. Though I would have to wonder how anyone would confuse them as a comet. My point is they are so well recognized that we overlook them.
Also known as the Seven Sisters, this little cluster rises in the east in the evening in September. By the first of February it is just past the meridian. Located in the constellation of Taurus the bull, the little cluster is to the right, or west, of the bigger V shaped Hyades cluster that makes up the head of the bull. The big bright star Aldebaron, a Tauri, is not a member of the Hyades cluster and is actually about half the distance to them. The stars that make up the Pleiades are about 425 light years away. It is thought they were formed 100 million years ago, making them 1/50 as old as our Sun.The majority of the stars are spectral type B stars, with a sprinkling of A's thrown in. There are some 14 of them at 6.5 magnitude making them right at naked eye limit, though some are brighter. Most of them, however, are 40 times brighter than our Sun. Alcyone, the brightest, is 1000 times more luminous. There is also a large number of Brown Dwarfs. These are stars whose mass is too small to start the nuclear reaction. They are considered pre main sequence stars and they are difficult to observe.. Twenty five percent of the stars in the cluster may be Brown Dwarfs. I have found widely varying estimates for the number of stars in the cluster. The cluster has two motions, one is dispersing, and the other is moving down and to the east. In several hundred millenia, it will be under Orion's feet., but its stars will have moved far apart by then.
Every month the Moon passes near the Pleiades. This February the first quarter Moon will pass 1.4 degrees S.S.E.of them on the eleventh. Binoculars is all that is needed to examine the Pleiades, and take your time and enjoy them. Count how many stars you can find.
At one time Lockheed Aircraft Company named Aircraft models after stars. There was a Lockheed Vega and Amelia Earhart's plane was a Lockheed Electra, named after 17 Tauri or Electra, which means the shining one, a star of the Pleiades.
Trivia: The only month in recorded history with no full Moon is February 1865, Abraham Lincoln was President.
Feb 02 Candlemas, or Groundhog Day. Six more weeks of winter.
04 Mars is in conjunction with the Sun, 11 AM. CST.
06 The Moon is 7 deg. above Uranus, 6PM. CST.
07 Jupiter is 7 deg. below the Moon 4AM. CST.
11 First Quarter Moon.
18 Full Moon.
24 Last Quarter Moon.
25 Mercury at superior conjunction 3AM, CST.
28 The Moon 1,6 deg. above Venus 10 PM, CST. Will also be above Mar. first.