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Let us begin
the sky watch of this month from North. Stand facing north and look
a bit above the horizon. Hold the map in such a way that the 'North'
on the map can be read correctly. You will see that the Ursa Major,
the Great Bear [Saptarishis], are fairly well above the horizon. Look for the star
Mizar (Vasistha). If you have good eyesight then it will not be
difficult for you to see its companion Alcor (Arundhati).
We are often asked to suggest some astronomy project for an absolute beginner. Try this - Mark all the seven bright stars of Uras Major, say as A, B, etc. and list the stars in ascending or descending order of brightness. This exercise will improve your observing skills of estimating magnitudes of stars. Next you can try seven bright stars in Orion. As we are talking about Orion, the Hunter [Mrugha], turn by almost 90 degrees counter clockwise (turn to your left). Orion is still above the horizon. Three stars almost on straight line that are boxed inside four other. The ruddy star at the upper right corner of the box is Betelgeuse (Kakshi). This star is so big that it will engulf almost half the solar system if kept at where the Sun is. Rigel (Rajanya) at the other corner is in contrast a very hot white star. Turning a bit to right and shifting your gaze a bit to lower side you can see what may be called a perfect alphabet in the sky 'V'. It is a Hyades cluster in Taurus, the Bull (Vrishabha). The red star at one end of this 'V' is Aldebaran (Rohini). Still further down is the another cluster of stars, the Pleiades (Kruttika), almost touching the horizon.
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Gemini, the Twins (Mithuna)
are about 45 degree above the western horizon. And a bit their south is Canis Minor. Identify two stars of Canis Minor,
Castor and Pollux making a big parallelogram. This is the Gateway of
Heavens.
A few years ago famous astrophotographer, Dr. David Malin was in Pune, He told me that Australian aborigines visualize these two groups as men and women sitting around a camp fire with men having their bigger share of fire, the red Aldebaran. He also told a very interesting aspect of astronomy of these people. Australians aborigines were afraid of darkness and they never ventured in the night. As a result they never used stars for navigation as was done by people from almost very civilized cultures. While on the issue of navigation, a very interesting constellation is now almost fully up above the southern horizon. Long ago it was called Argo Navis but now broken in three separate constellations. Puppis, the Stern; Carina, the Keel and Vela, the Sail of a ship. The brightest star in the constellation of Carina is Canopus. The star would have already set. It is also the second brightest star of the night sky. The brightest being Sirius, of course. It is still above the horizon. At zenith, that is right over head we have the majestic heavenly beast Leo, the Lion [Sinha]. If you could do the exercise of listing stars of Ursa Major try this constellation now.
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Some celestial events this month (time in UT = IST+5.5h)
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The
material here can be used freely. Site created on June 10, 2007 |
The
site is created for the
Public
Outreach Programme,
IUCAA by Arvind Paranjpye - arp@iucaa.ernet.in +91 20 2560 4601 Samir Dhurde - samir@iucaa.ernet.in +91 20 2560 4603 Updated on March, 2010 |