Astronomy news for the week starting Friday, February 19, 2010.
The week starts off with the
Moon in a fat waxing crescent phase,
with first quarter crashing in on the
night of Saturday, February 21, about as darkness falls, allowing
for a near-perfect quarter to be seen. The rest of the week then
finds the Moon waxing in the gibbous
phase as it heads towards full next
week, on Saturday the 28th. Be sure to watch the evening of
Thursday the 25th to see the Moon pass five or so degrees to the
south of bright
Mars, while at the same time pointed to by Pollux and Castor of Gemini, which will be to the west of the red planet.
So enjoy Mars, which crosses the meridian to the south around 10 PM as it
retrogrades in Cancer between
Gemini's two bright stars and the Beehive Cluster. Because Jupiter is gone, as it prepares to go through
conjunction with the
Sun next week. That leaves the weekly story, more or less,
with Saturn, which rises in Virgo at 8 PM, about two hours
before Mars crosses south. The ringed planet then transits before
2 AM. But then there is also
Venus, which is now bright, but in deep evening western
twilight and still hard to find. When you see it, you'll know it.
This is the prime season for great Orion, the celestial Hunter, the seven-star pattern
made obvious by his three-star Belt high to the south at 8 PM. To
the left is Canis Minor, his
smaller hunting dog illuminated by the star Procyon, the eighth brightest star
in the sky, mostly because it is just a dozen light years away.
Down and the left of the Hunter barks Canis Major, the Larger Dog, whose luminary Sirius outshines all other stars, its
sparkle the result of variable refraction in the Earth's
atmosphere. Closer than Procyon, it's just under nine light years
off. With these two, we sometimes forget another constellation that is associated with
the Orion myth, his little prey upon which he seems to stand, Lepus, the Hare, an attractive
double-box-like figure immediately to the right of Sirius. If you
have a good enough southern horizon, look below Lepus for the flat
triangle that makes modern Columba,
the celestial Dove.