December (Note: The names of the constellations are given in bold and the names in italics are the names of heavenly bodies in Indian astronomy. For better understanding take a print out of the map.) |
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Month of
December brings good crispy clear skies. These winter months are good for
sky watching and also are good for those who are beginning to learn to
identify the constellations because we have quite a few constellations
with very bright stars.
This month let us let us begin with the eastern direction. Face east and hold the map so that 'East' marked it is in the direction of your feet and 'West' is up (it will be read upside down). North will be to your left and South to your right. Orion, the Hunter [Mrugha] is an easy constellation to identify. There are three stars in a row placed almost at equal distance. Surrounding them are four other bright stars in rectangular formation. These seven stars make the basic Orion constellation. According to the Indian mythology Orion is Mrugha, the Stag. The four stars in the box formation make its front and hind legs and the three stars in middle are the marks of the trident thrown at it by Vyadha, the Killer. Orion in Greek mythology was the son of Neptune and the Amazon Queen Eurayale. He was an expert hunter and fighter. The three stars in a row make his belt. The stars to left and right make its arms and knees respectively. Chain of stars to the right of the belt is the Sword of Orion. This forms tail of Mrugha, the Stag. From the latitudes close to the equator such as ours this constellation may not appear as a giant standing figure to the most. But but then turn the map by 90 degrees and the figure will become clear to you. Orion is to be pronounced as 'or eye on' and not as 'o ri on' as many do in India. On the map you can see a star marked Betelgeuse [Kakshi]. It is one of the biggest stars knows to us. This ruddy colour star has diameter more than abuot 350 times that of the Sun. At the opposite corner of the square is Rigel [Rajanya]. It is one of the very intrincsically bright stars know to the astronomers. The star is about 14,000 times brighter than the Sun and its diameter is 35 time bigger. The star is about 870 light years from us. In the
sword Orion of lies one of the best nebulas (a cloud of gas and dust in
the medium between the stars). It is called the great Orion nebula.
This object looks impressive through telescope of any size. Using a pair
of binocular you can make out a faint bluish glow of this nebula and if
you have a small telescope then you can even make out some shape. This
nebulosity is about 1,500 light years from us. This nebula takes
magnification very will. Bigger the telescope impressive it looks. |
If you extend
the belt of Orion to upper right you will end up with a cluster of stars
in upside down 'V' shape. (I prefer to call it 'A'.) This is
Hyades cluster in the constellation Taurus, the
Bull [Vrishabha]. The red colour star is
Aldebaran [Rohini] that happens to be in the direction of
the cluster. The actual distance of the cluster from us is about 125 light
years where as Aldebaran lies halfway between at 65 light years from us.
Total span of Hyades is about 10 light years. That is at the speed of
light you will take about 10 years to cross from one end of the cluster to
the other. Further above Hyades is another cluster of stars Pleiades [Kruttika]. This cluster is about 400 light years from us and its spread is over 12 light years. I have told you how big these two clusters are and I have also given you the distance of Hyades from us. Now can you estimate how far Pleiades stars are from us? Rohini and Kruttika are 3rd and 4th Nakshatras respectively. Facing
north you can make out M-shaped constellation Cassiopeia
[Sharmishta]. to its left and above is the Flying Horse [Maha-ashwa]
and just above is Andromeda [Devayani]. Look for
the object marked M31. You should be able see it with your naked eyes.
From light polluted city try using a pair of binoculars. This is the Great
Andromeda Galaxy. It will appear as a fuzzy patch of light. Almost overhead is Cetus, the Wheal [Timingal]. See if you can trace out all the stars in this group. You may not be able to do so. Which one is missing? Mira is now fading. We tend to pronounce Mira as 'Mira' as in 'Mirabai'. It is to be pronounced as 'Myra' is now fading. Mira means beautiful. |
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Site created on June 10, 2007 |