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The Sky This Week, 2010 February 2 - 9

Snowscape delights
Mars, 2010 January 28, 03:53 UT
20-cm (8-inch) Schmidt-Cassegrain telescope

The Moon wanes in the morning sky this week, working her way through the springtime constellations as she travels down to the southern reaches of the Ecliptic.  Last Quarter occurs on the 5th at 6:48 pm Eastern Standard Time.  Luna starts the week in a triangular configuration with golden Saturn and ice-blue Spica before dawn on the 3rd.  The next morning she’s within five degrees of the star.  On the morning of the 7th, see if you can spot her waning crescent just over three degrees west of Antares, the reddish star that marks the heart of Scorpius, the Scorpion.

I cannot let Groundhog Day pass without relating the latest news flash from Gobbler’s Knob in Punxsutawney, Pennsylvania.  The official word from the world’s most famous marmot is that a shadow was observed, so there will be six more weeks of winter.  With the astronomical season of spring arriving on March 20th, this is practically a self-fulfilling prophecy.  A casual glance at the calendar will show that the equinox will fall in six weeks and four days.  With more snow forecast on the horizon, it may be a long six weeks after all.  However, there is something quite magical about stargazing from a snow-covered field.  Somehow the sky seems more transparent, and the stars seem to take on a new brilliance that accentuates their colors.  No better example of the different hues of stars can be found in any other season.  The bold figure of Orion, which now straddles the meridian at around 9:00 pm, draws your attention to the southern half of the sky where the stars of the Great Winter Circle silently wheel from east to west.  Most of The Hunter’s stars appear blue in color, with the noticeable exception of Betelgeuse, whose rose-colored tint contrasts with his companions.  To the left of the three Belt Stars, dazzling Sirius outshines all other luminaries in the night with its own flickering blue tint.  Moving clockwise from Sirius we pass the white glow of Procyon, the twin stars of Gemini, Castor and Pollux, and the bright golden hue of Capella close to the zenith.  Moving to the southwest we encounter the amber light of Aldebaran in Taurus before ending up at Rigel, Orion’s right knee.  Within the bounds of this circle of stars we find nine of the 25 brightest luminaries in the entire sky.  Just the thing to light your way home across snow-covered landscapes!

Jupiter lurks briefly in the evening twilight sky.  This week the giant planet sets before the end of astronomical twilight, effectively ending his telescopic observing season for the next few months.  He has one treat left for us, though, when he passes just half a degree from Venus in another two weeks.

Ruddy Mars is now the planet to command your attention in the night sky.  He’s on the meridian at midnight and visible in the sky all night long.  He’s very hard to miss since he’s situated in a rather barren part of the sky among the faint stars of Cancer, the Crab.  This week he passes several degrees north of the binocular “Beehive” star cluster as he drifts westward in his retrograde loop.  If you choose one week to hope for a good glimpse of him through the telescope, this is the one.  He’s beginning to inch away from Earth, but his disc is still close to its maximum opposition size.  In addition to his frosty white north polar cap, some of the planet’s most prominent dark features are turned our way during the late evening hours.  If you have a six-inch telescope, they should be easy to see in moments of steady air.


Golden Saturn now rises about four minutes earlier each night, and by week’s end he will enter the sky at around 9:00 pm.  The ringed planet drifts slowly westward among the stars of western Virgo, and he’ll spend most of the next several months in this relatively uncrowded area of the sky.