Sabtu, 02 Mei 2009

Why Must Sirius?

Sirius is the brightest star in the night-time sky with a visual apparent magnitude of -1.47. It is located in the constellation Canis Major. Sirius can be seen from almost every inhabited region of the Earth's surface (those living north of 73.284 degrees cannot see it) and, in the Northern Hemisphere, is known as a vertex of the Winter Triangle. The best time of year to view it is around January 1, when it reaches the meridian at midnight. Under the right conditions, Sirius can be observed in daylight with the naked eye. Ideally the sky must be very clear, with the observer at a high altitude, the star passing overhead, and the sun low down on the horizon.

The name Sirius comes from the Latin sirius. It is situated in the eye of the greater dog Canis Major, therefore it is known as the 'Dog Star'. Other meanings:

What to the eye appears as a single star is actually a large binary star system, consisting of a bright white main sequence star of spectral type A1V, named Sirius A, and a faint white dwarf companion of spectral type DA named Sirius B.

Sumber : http://www.crystalinks.com/sirius.html


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