The first day of December starts with a new moon. The waxing crescent moon is below Venus on Dec. 4. The waxing crescent passes Saturn in the south on Dec. 7. It is first quarter on Dec. 8. The full moon, the Yule moon, is north of Jupiter on Dec. 15. The moon misses Mars, passing its half-degree diameter north of it at 3 a.m. on Dec. 18. The Winter Solstice, the shortest day, occurs at 3:21 a.m. CST on Dec. 21. The last quarter moon is on Dec. 22. The waning crescent moon makes a spectacular triangle with Antares and Mercury in the dawn of Dec. 28. The new moon is Dec. 30.
Mercury will become visible in the dawn at the end of the month. Venus dominates the southwest evening sky, at magnitude -4.2 bright enough to be seen now in broad daylight. Mars is in the morning sky in Cancer and has a very close encounter with the moon on the morning of Dec. 18. Jupiter is at its best, reaching opposition on Dec. 7, rising at sunset and up all night. Here it is a fine shot of it by Marc Glover from Oct. 25 from Pace. Note the earth-sized Great Red Spot to the left-center on the oblate disk. Jupiter spins so fast, with just ten hours of rotation, that its polar diameter is 10% less than around its equator. Will happen to you, too, younguns.
This was a great evening to be an astronomer, for on the same night, Freddy Bowles in Milton took his fine shot of Saturn and its almost edge-on rings, and Floyd Griffith in Graceville caught Comet Tsuchinshan-ATLAS 2023 A3 with a bright meteor in the same photo. What a gallery EAAA has to share with our readers this month!
Saturn is well up in the south now at sunset, in Aquarius. Here Freddy Bowles captures its rings, now tilted 5 degrees to our line of sight, on October 25. By Jan. 7 they will narrow to 4 degrees, and just 3 degrees by Jan. 28. The rings will be edge-on from Earth between March 23 and May 6, but it will be lost then in the Sun’s glare or just reappearing in the dawn. Note the large moon Titan, bigger than Mercury, to the lower right of the planet here.
Visit the SkyMaps and download the map for December 2024.
The square of Pegasus dominates the western sky. South of it are the watery constellations of Pisces (the fish), Capricorn (the Sea Goat), Aquarius (the Water Bearer) with Saturn now, and Cetus (the Whale). Below Aquarius is Fomalhaut, the only first-magnitude star of the southern fall sky. It marks the mouth of Pisces Australius, the Southern Fish. If you want an ideal app for learning the constellations, download Nocturne for Apple phones, and mount it on a tripod for 2’ exposures of the sky, which you can then annotate with star names, constellation lines, and even the mythological figures. Makes the sky come alive.
The constellation Cassiopeia makes a striking W in the NW. She contains many nice star clusters for binocular users in the outer arm of our Milky Way, extending to the NE now. Her daughter, Andromeda, starts with the NE corner star of Pegasus’ Square and goes NE with two more bright stars in a row. It is from the middle star, beta Andromeda, that we proceed about a quarter the way to the top star in the W of Cassiopeia, and look for a faint blur with the naked eye. M-31, the Andromeda Galaxy, is the most distant object visible to the naked eye, lying about 2.5 million light-years distant.
Overhead is Andromeda’s hero, Perseus, rises. Perseus contains the famed eclipsing binary star Algol, where the Arabs imagined the eye of the gorgon Medusa would lie. It fades to a third its normal brightness for six out of every 70 hours, as a larger but cooler orange giant covers about 80% of the smaller but hotter and thus brighter companion as seen from Earth.
Look at Perseus’ feet for the famed Pleiades cluster; they lie about 400 light-years distant, and over 250 stars are members of this fine group.
Yellow Capella, a giant star with the same temperature and color as our much smaller Sun, dominates the overhead sky. It is part of the pentagon on stars making up Auriga, the Charioteer. Several nice binocular Messier open clusters are found in the winter Milky Way here. East of Auriga, the twins, Castor and Pollux highlight the Gemini.
Last but certainly not least, in the east rise the hunter’s two faithful companions, Canis major and minor. Procyon is the bright star in the little dog and rises minutes before Sirius, the brightest star in the sky. Sirius dominates the SE sky by 7 p.m., and as it rises, the turbulent winter air causes it to sparkle with shafts of spectral fire. Beautiful as the twinkling appears to the naked eye, for astronomers this means the image is blurry; only in space can we truly see “clearly now”. At eight light years distance, Sirius is the closest star we can easily see with the naked eye from West Florida. You must be in South Florida to spot Alpha Centauri on June evenings. Below Sirius in binoculars is another fine open cluster, M-41, a fitting dessert for New Year’s sky feast.
Our final public planetarium show of 2024 is on December 6, at 6 p.m. in the Space and Science Theatre. “Let It Snow” is a fine celebration of the season, and our EAAA Christmas dinner follows at 7 p.m. in room 1709 at Pensacola State College. Get your tickets at Purple Pass early; the last five shows have all been SOLD OUT.
On the Saturdays of the first and third quarter moon, we continue our cooperation with the Florida State Parks at Big Lagoon State Park. Normal entry fees ($6 per car) to Big Lagoon still apply, and remember to check in the front gate before it closes at sunset (5 p.m. currently). Clear skies permitting, we will set up on December 7 & 21, January 4 & 25, February 8 & 22, and March 8 & 22. We return to Pensacola Beach Pavilion gazes on April 4.
For more information on the Escambia Amateur Astronomers, visit us on Facebook or contact our sponsor, Lauren Rogers at lrogers@pensacolastate.edu. Contact me by email at johnwaynewooten@gmail.com. All EAAA events are free and open to the public.
