Astronomy news for the week starting Friday, February 10, 2012.
We begin with the Moon in its waning
gibbous phase, which leaves the evening over to darkness.
Moving along through Virgo into
Libra, the Moon arrives at its third quarter on Tuesday, February 14
(helping to celebrate Valentine's Day) during daylight hours in
North America. It thereafter spends the remainder of the week as
an ever-slimming waning crescent. The
night of Friday the 10th finds the Moon to the southeast of Mars. Then look
later in the night of Sunday the 12th when the Moon passes several
degrees south of Saturn and
nearby Spica, the star the fainter
and southwestern of the two. Near the beginning of our week, on
Saturday the 11th, the Moon goes through perigee, where
it is closest to the Earth.
As it will for the rest of winter and for much of spring, Venus claims the early evening sky. High to
the west at twilight, the brilliant planet, which dominates all
others, does not now set until 9 PM, two hours after dusk finally
fades away. Following behind is the second of the planetary
lights, Jupiter. To the
east of Venus (you can't miss it), the giant planet does not meet
up with the horizon until half an hour before midnight. As Venus
goes down, it is replaced in the opposite side of the sky by Mars,
which rises around 7:30 PM in a fine setting in southeastern Leo
rather between Leo's Regulus and Virgo's Spica, which is
course leads us back to Saturn, which comes up just before Jupiter
sets. Mars then transits the meridian
to the south around 2 AM, Saturn around 4:30, the bright stars and
planets making a delightful sight in the morning sky.
Aside from the planets, the focus this time of year must be on Orion, which stands mightily to the
south around 8:30 PM, his three-star Belt (the Arabs' String of Pearls) always striking. To
the upper left is the red supergiantBetelgeuse, to the lower right
the blue supergiant Rigel. Hanging
from the Belt is the Sword, which encloses the famed Orion Nebula, a marker of recent,
indeed ongoing, star formation. The area provides a rich field of
sights for the telescopic, even binocular, visitor.
Much of the constellation is a part of the
"Gould
Belt", a ring of bright stars somewhat offset from the Milky Way that is named after B. A. Gould,
an astronomer of the nineteenth century.