The Sky This Month – February 2013

SaturnComet PANSTARRS creeps into the early-morning sky for southern-hemisphere observers.  Mars and Mercury make a picturesque appearance with the crescent Moon.  And Saturn’s rings cast a long shadow on the planet’s cloud tops for observers up early with a telescope.  Here’s what to see in the night sky this month…

1-8 February.  Early this month, and also at the end of the month, northern hemisphere observers can see the zodiacal light.  This eerie glow, caused by sunlight reflecting off dust in the solar system, looks like a tall pyramid of light sloping to the left.  Look for it in the western sky about 90-120 minutes after sunset.  Very dark and clear sky is required.

3 Feb.  Also in early February, southern-hemisphere observers can see, with binoculars, Comet C/2011 L4 (PANSTARRS).  This is one of two bright comets on the way this year.  Shining at 6th magnitude, this comet has so far been an underperformer.  From the deep south, look for the comet near the star Arkab (beta Sagittarii), which itself is a pleasant double star for binocular observers.  The map below shows the comet on Feb. 3 as seen from 35ºS latitude at dawn.  It moves about 4° towards the horizon each day.  Northern-hemisphere observers will have to wait until next month to see the comet.

The location of Comet C/2011 L4 (PANSTARRS) on Feb. 3 about an hour before sunrise as seen from 35 S latitude.  Click to enlarge.

The location of Comet C/2011 L4 (PANSTARRS) on Feb. 3 in the southeastern sky about an hour before sunrise as seen from 35 degrees south latitude. Click to enlarge.

3 Feb.  The last-quarter Moon is just to the southeast of the planet Saturn in the early morning sky about an hour before sunrise.  Saturn’s rings cast a lovely shadow this month for those up early with a telescope.  Saturn is south of the ecliptic for the next many years, so southern hemisphere observers get to see the ringed planet fairly high in the sky compared to us northerners.

3 Feb.  Last-quarter Moon, 13:56 UT.

7 Feb.  Mars comes within 0.6º of Mercury low in the southwestern sky just after sunset.  They are a fine site in binoculars!  The two are even closer together on Feb. 8.  Mercury is the brighter of the two.

10 Feb.  New Moon, 7:20 UT.

11 Feb.  Look for Mercury and Mars near a slender crescent Moon about 30 minutes after sunset.

Mercury, Mars, and the crescent Moon after sunset on Feb. 11, 2013.  Click to enlarge.

Mercury, Mars, and the crescent Moon after sunset on Feb. 11, 2013. Click to enlarge.

12-18 Feb.  Mercury reaches nearly 10º above the southwestern horizon just after sunset.  This is an excellent opportunity to see this little planet with your unaided eye or binoculars.

18 Feb.  The Moon and brilliant Jupiter dance again as they have in the past several month.  These two, along with the bright-orange star Aldebaran make a tight triangle, with the splendid Pleiades star cluster nearby.

17 Feb.  First-quarter Moon, 20:31 UT.

25 Feb.  Full Moon, 20:26 UT.

28 Feb.  The Moon comes very close to the bright star Spica in the constellation Virgo.  Look for the pair in the eastern sky around midnight.