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Groundhog Day...Again?

by Geoff Chester, USNO Public Affairs | 30 January 2024

by Geoff Chester, USNO Public Affairs | 30 January 2024

NGC2264, the "Rosette Nebula" in Monoceros (with embedded star cluster NGC2244)
imaged 2021 March 7 at Sky Meadows State Park, Paris, Virginia
with an Explore Scientific AR102 10.2-cm (4-inch) f/6.5 refractor
and a ZWO ASI183MC CMOS imager.

The Moon wanes in the morning sky this week, diving southward along the ecliptic as she courses her way through the rising spring constellations.  Last Quarter occurs on the 2nd at 6:18 pm Eastern Standard Time.  If you are up during the wee hours on the morning of the 1st, look for the bright star just below Luna’s gibbous disc.  This is Spica, brightest star in the sprawling constellation of Virgo.  On the morning of the 4th the Moon’s waning crescent moves through the stars that form the “head” of the summer constellation of Scorpius.  The Moon ends the week near the bright glow of Venus as morning twilight brightens the sky.
February 2nd is Groundhog Day, once a quaint local observance that now attracts near world-wide attention.  The date has roots that go back well over 1000 years when traditional feudal calendars were anchored by the astronomical seasons.  Between the “quarter days” marked by the equinoxes and solstices there were “cross-quarter days” that marked the mid-points of seasons.  Each of these days were times of feasts and rituals dedicated to pagan gods.  As Christianity spread through Europe these dates were adapted to celebrate various saints or events.  Imbolc, the cross-quarter day celebrated around February 1st, became associated with Candlemas, the feast celebrated 40 days after Christmas.  German-speaking people maintained a ritual from pre-Christian times in which they saw badgers emerging from their dens.  If the weather was clear and cold, the animals returned to hibernation.  The ritual came to America with the so-called Pennsylvania Dutch immigrants, who replaced the badger with the native woodchuck.  It was observed locally in the eastern United States until 1993, when a popular movie introduced it to the world.

The February citizen-science observing campaign for the Globe at Night program begins on the evening of the 1st.  This is a great opportunity to contribute a bit of data for science and to sharpen your sky-watching skills.  The target constellation is Orion, the Hunter, which is ideally placed in the evening sky as well as visible from just about anywhere on the planet, even under urban skies.  Orion boasts a number of first- and second-magnitude stars as well as a good selection of fainter luminaries to help you determine the relative brightness of your observing sight.  You will find observing tips and reporting information on the program’s website.

In addition to Orion, take the time to explore other regions of the Great Winter Circle.  If you happen to be at a dark location, look between the bright star Capella at the top of the circle and the dazzling glow of Sirius, the brightest star in the sky.  In this area you may notice the faint diffuse glow of the winter Milky Way.  Unlike the summer sky, where we are looking toward our galaxy’s center, at this time of the year we are gazing in the opposite direction toward the Milky Way’s nearest edge.  This area is a wonderful part of the sky to look at with a small, wide-field telescope.  Just to the left of Orion is the obscure constellation of Monoceros, the Unicorn, one of the more “modern” constellations, introduced in star atlases in the 17th Century.  What it lacks in stars Monoceros makes up in knots of stars and glowing nebulosity.  Its most striking feature is the Rosette Nebula, a softly glowing gas cloud surrounding a bright knot of stars.  Dark skies are necessary to see it; its apparent diameter is about twice that of the full Moon.  If you’d like a chance to see it for yourself, come out to Sky Meadows State Park near Paris, Virginia on the evening of the 3rd.  The monthly “Astronomy for Everyone” program will feature dozens of telescopes provided by local amateur astronomers.

It is time to bid Saturn a warm farewell.  The ringed planet may still be glimpsed low in the southwest during evening twilight, but by the end of February he’ll pass behind the Sun.

Jupiter still dominates the early evening sky, but he now sets at around midnight.  Old Jove is easy to find, but if you want a good view through the telescope try to catch him as early as possible. 

Venus now rises just as morning twilight begins.  Your best view of her will be about 45 minutes before sunrise, when she will be some 10 degrees above the southeast horizon.  Look for the slender waning Moon below Venus before dawn on the 7th.


Commander, Naval Meteorology and Oceanography Command | 1100 Balch Blvd. | Stennis Space Center, Mississippi 39529

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