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Touring the Winter Circle

by Geoff Chester | 23 January 2024

by Geoff Chester | 23 January 2024

Messier 42, the heart of the Great Nebula in Orion, imaged 2024 January 3 from Alexandria, Virginia
with a Celestron 23.5-cm (9.25-inch) f/10 Schmidt-Cassegrain telescope
and a ZWO ASI183MC CMOS color imager

The Moon beams down from a high perch among the stars of winter as the week opens, then drops southward to join the rising constellations of spring.  Full Moon occurs on the 25th at 12:54 pm Eastern Standard Time.  January’s Full Moon is widely known as the Wolf Moon, a tradition brought over to America by northern European settlers whose ancestors noted the howling of hungry wolves during the lean times of mid-winter.  One Celtic tradition calls it the Stay Home Moon, while some Native Americans called it the Severe Moon.  Despite these dire-sounding names, Luna adds welcome brightness to snow-covered landscapes.  Look for the Moon near the stars Castor and Pollux, the Twin Stars of Gemini, on the evenings of the 23rd and 24th.  On the evening of the 27th she rises just east of the bright star Regulus, the “heart” of Leo, the Lion.

The Full Moon washes out many of the fainter stars that dominate the western sky during the early evening, but by 9:30 pm the brilliant stars of the Great Winter Circle dominate the celestial scene.  At this time the meridian seems to cleave the Circle in two.  Despite the bright moonlight, this is a splendid part of the sky to explore with binoculars or a small telescope.  The brightest stars have a beautiful range of colors, ranging from the ruddy glow of Betelgeuse in Orion and Aldebaran in Taurus to the icy blue dazzle of Sirius and the golden yellow tint of Capella in Auriga.  Each of these constellations have a number of interesting objects to scan that defy the brightness of Luna.

Let’s start our tour with Sirius, the brightest star in the night sky.  Just a few degrees south of the star you will find a scattering of stars that form the galactic star cluster Messier 41.  Binoculars will show the brighter members, but a 4-inch telescope will show up to 100 members.  

Following a line from Sirius through Orion’s three bright “Belt Stars” will bring you to Aldebaran, the ruddy “eye” of Taurus, the Bull.  This bright star sits at the end of one of the tines of the V-shaped group known as the Hyades.  In mythology these were the half-sisters of the Pleiades, located about 10 degrees to the northwest.

At the top of the circle you will find the yellow-tinted star Capella, the brightest member of the constellation of Auriga, the Charioteer.  Auriga resembles a flattened pentagon, and within this shape are three prominent star clusters, numbers 36, 37, and 38 in Charles Messier’s catalog.  Binoculars will show them as fuzzy patches, but they will resolve nicely in a 4-inch telescope.

Finally, let’s return to the central figure in this part of the sky, the dazzling constellation of Orion, the Hunter.  A casual glance through binoculars will bring out the intense blue tints of most of the Hunter’s bright stars, with one almost glaring exception.  Ruddy Betelgeuse is the outlier.  All of Orion’s bright stars are supergiants, cosmically young stars pumping out thousands of times the light and energy of our Sun.  These stars will churn through their nuclear fuel in a matter of a few tens of millions of years, and Betelgeuse is a preview of their ultimate fate.  It is a vast, bloated luminary that has exhausted its fuel and is nearing the end of its life.  The star’s diameter is larger than the orbit of the Earth, and its tenuous outer layers glow with its characteristic red tint.

All of Orion’s stars seem to have originated in a small asterism that hangs just below his “belt”.  Here your binoculars will show three groupings of stars, with the middle one showing a distinctive “fuzzy” appearance.  This is the Great Orion Nebula, a stellar nursery rife with proto-stars and clouds of gas and molecular compounds.  It is one of the most spectacular sights in the sky for the small telescope, a bright, mottled glow surrounding four central blue stars.  Wisps of glowing gas and tendrils of darkness crisscross the nebula’s heart, and the more time you spend looking at it the more detail you can see.  There’s enough material there to produce some 10,000 solar mass stars!

Saturn is now bidding us a long good-bye.  The ringed planet now sets at around 8:00 pm local time.  Look for him low in the southwest as evening twilight falls.

Jupiter appears on the meridian shortly after sunset and still lords over the evening hours.  The giant planet remains the brightest object in the evening sky after the Moon, and he will continue to be a treat for telescopic observers for several more weeks.

Venus is now moving through her southernmost declination for the year.  You can spot her low in the southeast.  She rises just before the beginning of morning twilight, but you should have no trouble spotting her glow right up until sunrise.


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

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