Astronomy news for the week starting Friday, March 5, 2010.
Want to see the Moon? Then you'll have to be up late. Starting in
the waning
gibbous, it passes third quarter on
Sunday, March 7, when it will not rise until after midnight.
Afterwards, in the waning crescent, it
rises ever later, until it finally disappears at new phase next
week, on Monday the 15th.
And it puts on a good show. The morning of Saturday the 6th, it
will shine within the southern part of the three-star head of Scorpius to the west of Antares. By the following morning,
it will (at its rate of 13 degrees per day) have flipped to the
east of the star. Then it's Sagittarius's turn, the Moon spending the next three
mornings passing the celestial Archer. The morning of Tuesday the
9th, look for it just north of Sagittarius's five-star "Little Milk Dipper." Even the morning
of Friday the 12th will give you a view of the thinning crescent.
That same day, the Moon goes through apogee, where it is farthest from Earth.
While
Jupiter is gone from sight,
Saturn is still nicely there. Rising in mid-twilight amidst
the fainter stars of Virgo to the
east of the autumnal equinox,
the planet plies the eastern sky until it transits the meridian to the south at 1 AM, after
which it descends the western heavens.
Beyond that, the sky is beholden to the planets that bracket the
Earth:
Venus and Mars. Venus is
so luminous that it should be visible in bright western twilight,
setting about half an hour before the sky gets truly dark. Mars on
the other hand, transits the meridian around 9 PM, some two hours
after Venus sets. The red planet is so far north, still to the
east of Gemini's Castor and Pollux, that it does not set until
the advent of dawn. Mars also makes special news, as it ceases its
retrograde motion the night of Wednesday the 10th. It will
thereafter begin to swing with ever increasing speed to the east
against the stars. Given that the Earth only slowly pulls ahead of
it in orbit, this most-Earthlike planet will be visible in the
western sky until late summer.
'Tis the prime season for glorious Sirius, the luminary not just of Canis Major, but of the entire sky,
the star seen now to the south at 8 PM. Well below it, those in
the deep south might be able to catch the second brightest star, Canopus, the luminary of Carina, the Hull of ancient Argo, the Ship of the Argonauts, which
sails below and to the east of Orion's Larger Dog. Far above, Auriga, with Capella,
the most northerly first magnitude star, slips west along with the
rest of winter's gang.
