Showing posts with label Hyades. Show all posts
Showing posts with label Hyades. Show all posts

Friday, December 20, 2013

BULL'S EYE!

Taurus the Bull is easy to identify even in light polluted skies. Orion's belt stars make good pointers. Connect the three dots and continue the line of sight up and to the right and you will arrive at a small "V" shape of stars. That is Taurus' face. The brightest star in the "V" is the Bull's Eye, a red giant called Aldebaran. Aldebaran means "the follower," but what is it following? If you continue the line from Orion's belt through the "V" you will see. The Seven Sisters (or Pleiades) is just to the west. As the night goes on Aldebaran follows the Sisters through the sky.
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Inside the "V" are a lot of stars. This is called the Hyades star cluster (in Greek mythology five of these were the half-sisters to the Pleiades) ((wait a second... seven plus five... that's a lot of kids for the god Atlas to raise!). The Hyades are the closest open cluster to Earth at only 150 light years distant. You can observe dozens to hundreds of these stars with a good pair of binoculars. Aldebaran is not a Hyade, though. It is much closer to the Earth and just appears in the same neighborhood.
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Off the top of the "V", the horns of the bull radiate out to the stars Elnath and Zeta Tauri. Next to Zeta Tauri is one of the most interesting objects in space. Named M1 or the Crab Nebula, this is the remnant of one of the brightest stellar explosions ever witnessed by humans. M1 is the leftover of a supernova explosion that erupted in 1054 AD. The blast was so bright that it was visible during the daytime along with the Sun. Since then we've had two other bright supernovas (1572 and 1604). I think we're due. And maybe, fingers crossed, we'll see Betelgeuse go "KABLOOEY!"

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Monday, November 26, 2012

TAURUS THE BULL

Taurus the Bull is easy to identify even in light polluted skies. This year you have a extra bright clue to help point your way.  The giant planet Jupiter is hanging out in the bull's horns and you can't miss it.  Look east after sunset and Jupiter will be the brightest starlike object.

Just to the right of Jupiter is a bright star that should look a little orange.  That's the Bull's Eye star called Aldebaran.  Fainter stars nearby make a "V" shape with Aldebaran and represent the bull's face.  Aldebaran means "the follower," but what is it following? If you look about 15 degrees above Aldebaran you will see a little cloud of stars.  Those are the Seven Sisters (aka the Pleiades).  As the night goes on, Aldebaran follows the Seven Sisters through the sky.

See the "V"?
Inside the "V" are a lot of stars. This is called the Hyades star cluster (in Greek mythology five of these were the half-sisters to the Pleiades) ((wait a second... seven plus five... that's a lot of kids for the god Atlas to raise!)). The Hyades are the closest open cluster to Earth at only 150 light years distant. You can observe dozens to hundreds of these stars with a good pair of binoculars. Aldebaran is not a Hyade, though. It is much closer to the Earth and just appears in the same neighborhood.

In November and December you can see Jupiter and Taurus all night long. In the evening they'll be in the east.  Around midnight they'll be high in the south.  And before dawn, they'll be setting in the west.  Check them out and watch Aldebaran "following" those Seven Sisters!

Shameless, eye-catching picture of Jupiter

Wednesday, February 15, 2012

Tale of Two Clusters in Taurus

Hyades - Do you see the "V?"
Don't worry, Taurus the Bull isn't sick.  He's just got a cluster of stars on his face and another cluster on his back. 

Finding the Bull is pretty easy.  Look for a long, skinny “V” shape above and to the right of Orion. The “V” marks Taurus’ head and long horns as he is about to trample brawny hunter.

If you are still having trouble, find the three stars which mark Orion’s belt and use them as pointer stars. Connect the three dots and continue this line to the right. This line will take you just under a bright, orange-colored star. That is Aldebaran, or the bull’s eye.

How you find the clusters
You'll notice Aldebaran is redder than other stars – “A ruby of dazzling hue.”  And if you look closely you'll see lot of fainter stars all around Aldebaran and the "V" shape.  These are the Hyades star cluster.  All of these stars (except Aldebaran) are about the same distance away and were formed from the same nebula.  They're the closest open cluster in the skies and that's why you can see them with the naked eye.  The ancient Greeks thought they were the five daughters of Atlas who cried all the time over the death of their brother Hyas.  Ever since then, the Hyades have been associated with rainy seasons.   

The name Aldebaran is an Arabic word loosely translated as “The Follower”. What is Aldebaran following? Just continue that line from Orion’s belt past Aldebaran and you will see the most impressive cluster of stars, the Pleiades.

Close up of both clusters
 Maybe you’ve heard of the Pleiades from their alias, the Seven Sisters. At first glance, the stars in the Pleiades look more like a little cloud the size of the full moon. But upon closer examination, you may detect five, six, or seven individual stars in the group. With binoculars you can see approximately 50 stars in the cluster, and with a telescope you can count all 500 of them.  We'll talk more about the Seven Sisters next week, so tune in!