Tuesday, August 31, 2010

Venus has two companions

The closest planet to our Earth is currently Venus. This similarly sized world as our own is shining brightly in the west-southwest directly after sunset. Tonight it will have two companions with it: the brightest star in the constellation Virgo, Spica, and the red planet Mars. Spica will be just above Venus while reddish Mars lies to its right. Wait until 8:40 p.m. when the sky is dark enough before viewing them. Otherwise, the twilight will be too bright, obscuring the dimmer Spica and Mars.

On the evening of September 1, Venus will be just to the lower left of Spica. Mars remains to their right.

Such is our view from Earth...

Saturday, August 28, 2010

Bright Jupiter and much dimmer world

The end of August and the beginning of September sees bright Jupiter climbing in the east as evening darkness falls. By 10 p.m. it is an unmistakable object. For a bonus, aim a pair of binoculars at the bright planet. Half way towards the edge of the field of view to the upper right lies a star. A star it is not. That is Uranus, the seventh planet from the sun.

If you look closely, you will notice that Jupiter shows a tiny disk, while Uranus is mere a pinpoint. That is because Uranus is about five time farther away and only one-third as wide.

Such is our view from Earth.