Go Stargazing! February Edition

Venus continues to dominate the western sky on February evenings.  Look west-southwest right as night falls for the brightest thing there except for the Moon, which is nearby at the end of the month.  Venus, on its faster orbit, is coming around to our side of the Sun (and will pass us in March).  Therefore Venus is about as bright as it can be this month. 

Saturn is now a late evening object, rising in the east by 9 p.m. now and by 7 p.m. at month’s end.  Early next month, it will be opposite the Sun in the sky and be visible all night long. 

Mars and Jupiter are lost in the Sun’s glare much of this month.  They form a close conjunction on the morning of February 17, but the pair rises right as the twilight begins to brighten the sky that morning.  Mercury joins them later in the month. 

Dazzling Orion rises in the east, reminding us that winter is here.  His belt points up to Aldebaran, the eye of Taurus, the Bull.  The Dog Stars Sirius and Procyon are below Orion in the east.  Sirius is the brightest star we ever see at night.  To Orion’s left as he rises are two stars of similar brightness less than five degrees apart.  These are Castor and Pollux, marking the heads of Gemini, the Twins. 

Moon
Creative Commons License photo credit: Fingerz


Moon Phases in February 2009:

1st Quarter             February 2, 5:12 pm
Full Moon               February 9, 8:49 pm
Last Quarter           February 16, 3:38 pm
New Moon             February 24, 7:35 pm

The Full Moon of February 9 almost enters the Earth’s shadow.  It does enter a region of space called the penumbra, in which the Earth partially blocks the Sun.  This event is thus called a penumbral eclipse.  However, it begins right as the Moon is about to set here in Houston.  What’s more, a penumbral eclipse is only a slight darkening of the Moon, barely noticeable in the darkest skies.  In the morning twilight of February 9, you won’t see much of any difference in the Moon as it sets.

IMG_0959
Creative Commons License photo credit: S1lvers Family


Punxsutawney Phil saw his shadow on Groundhog Day, meaning six more weeks of winter.  What does this have to do with astronomy?  Well, Groundhog Day occurs about halfway between the winter solstice and the vernal (spring) equinox.  It therefore occurs near one of the cross-quarter days, called Imbolc by the Celts.  The other three are at the beginning of May, August, and November, and they represent points halfway between the quarter days, which are the equinoxes and solstices. 

Since we don’t want Phil to see his shadow, we clearly don’t want sunshine on February 2.  If this seems ‘backwards,’ consider that there is another day when we don’t want sunshine or warmth-Christmas. 

Houstonians still fondly recall our Christmas Eve snowstorm of 2004, while a similar snowfall on January 24 would have been much less romantic.  The French have the saying, “Christmas on the balcony, Easter by the fireplace.”  Early pagans considered the winter solstice and Imbolc symbols of winter itself.  If these days were appropriately wintry, with clouds and cold, then it was a sign that all was in order.  Winter, which was happening on time, would end on time.  However, if these days were not appropriately wintry, then something was wrong, and a ‘remedial’ winter would need to occur in springtime.  The traditions of the winter solstice and Imbolc were transferred to Christmas and Groundhog Day, respectively.  Thus, sunny weather (with shadows) is a bad omen on Groundhog Day, while cloudy weather (no shadows) is a good omen.