After
Sunset in the western twilight sky we see a bright star outshining
all the starts in the evening sky, this is the planet Venus. The
visual apparent magnitude of the planet Venus is now -4.6 and the
apparent magnitude of brightest star in the night sky, Sirius, in the
constellation of Cains Major is -1.46 this makes Venus 18 times
brighter than Sirius.
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| Brocken Inaglory, Venus-pacific-levelled, CC BY-SA 3.0 |
On February 17th Venus will reach its brightest
crescent phase and this is called Greatest Illuminated Extent, the
amount of illuminated crescent and the angular diameter of the planet
Venus. Venus will have an angular diameter of 39 arc seconds and
fraction of illumination is .273 of the angular diameter. After this
day the illuminated side will start decreasing and we will see the
crescent getting thinner. By second week of March the illuminated
fraction will be only .085 of the diameter of the planet and
magnitude would have come down to -4.4 still brightest in the evening
sky.
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| View Through the Telescope on 17th of Feb |
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| View Through the Telescope on 10th March |
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The planet Venus will slowly fade into glare of the Sun and will
reach inferior conjunction on March 25th. In April we
will see Venus in early morning sky before sunrise and again the
Greatest Illuminated Extent will happen on April 30th.
Time to take out the telescopes and observe Venus in coming days, if
you don't have one you are always welcome at ABAA on Sundays evening
and see the Venus through our telescope. Venus sets at 9pm now and
in middle of March the planet will set at 7:30pm.
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