The earth is closest to the Sun on Jan. 2, 2024, at 7 p.m. as our orbit is almost circular, the slight change from perihelion to aphelion in July (about 94 million miles) is so small that our 23.5-degree axial tilt plays a much larger role in our modern seasons. At times, precession will shift the coldest days of winter to aphelion (for instance, the last Ice Ages, 11,000 years ago).
The crescent moon will occult the bright red giant Antares in Scorpius for observing in the western U.S. before sunrise on Jan. 8. The brilliant planet Venus will be just northeast of the pair. The next morning, it will lie south of fainter Mercury in the twilight. Look closely with binocs and you may also spot Mars coming out from behind the Sun into the dawn. New Moon is Jan. 11; three more new moons to the April 8 total solar eclipse. More on that later, of course. The slender crescent lies below Saturn on Jan. 13, and above it on Jan. 14. The first quarter moon is on Jan. 17, and it passes below Jupiter the following evening. The full moon, The Snow Moon, is on Jan. 25.
For a detailed map of northern hemisphere skies visit Skymaps.com and download the map for January 2024;
Mercury is in the dawn most of January, to the lower left of Venus. It is at greatest western elongation, 24 degrees in front of the rising Sun, on Jan. 12, and heads back to the far side of the Sun. It merges with Mars in the dawn on Jan. 27, only .3 degrees above the Red Planet. Use binoculars about 40 minutes before sunrise. By month’s end, Mercury is lost in the Sun’s glare, and Venus too is getting lower and lower in the dawn. It will pass behind the Sun by Spring. Mars will slowly climb high in the dawn for the next several months.
Jupiter is well up in the southern sky at sunset, well placed for telescopic observations of its four Galilean moons and famed Great Red Spot. Saturn is low in the Southwest in Aquarius by month’s end and will be lost in the Sun's glare by the end of February.
The constellation Cassiopeia makes a striking W in the northwest. Her daughter, Andromeda, starts with the northeast corner star of Pegasus’ Square and goes northeast 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. Between him and Cassiopeia is the fine Double Cluster, faintly visible with the naked eye, and two fine binocular objects in the same field.
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.
South of Gemini, Orion is the most familiar winter constellation, dominating the eastern sky at dusk. The reddish supergiant Betelgeuse marks his eastern shoulder, while the blue-white supergiant Rigel stands opposite on his west knee.
Just south of the belt, hanging like a sword downward, is M-42, the Great Nebula of Orion, an outstanding binocular and telescopic stellar nursery. It is part of a huge spiral arm gas cloud, with active star birth all over the place. You should be able to glimpse this stellar birthplace as a faint blur with just your naked eyes, and the larger your binoculars or telescope, the better the view becomes. While M-42 is an emission nebulae, shining reddish from the ionization of its hydrogen gas by hot young stars forming inside it, the famed Horsehead south of the belt of Orion is a dark nebula, a dust cloud lying in front of the red glowing background hydrogen. Just north of it is the much easier Flame Nebula, in the same field of view as Mintaka, the eastern member of the belt. It is also an emission nebula. But the blue color around Mintaka is a reflection nebula, scattering the shorter wavelengths of the interstellar dust, just as small particles in our atmosphere scatter shorter blue waves best, making our sky blue. This is called Rayleigh scattering.
Enjoy such star spectacles while you can. This whole Orion molecular cloud is rich in dust as well as hydrogen to churn out new, very luminous blue stars like the ones that dominate the naked eye constellation. The horsehead’s dust is collapsing into protostars, and their heat and light will soon destroy the famed profile. Even the flame is not everlasting, but its shape and brightness will vary as new stars are born in the dark “wick” to expand the flames still brighter. M-42 also is constantly changing!
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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 southeast 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. Below Sirius in binoculars is another fine open cluster, M-41, a fitting dessert for New Year’s sky feast.
We have set new dates for our public gazes at Big Lagoon State Park west of Pensacola for these Saturdays: January 6 and 20, February 3 and 17, and March 2 and 16. Be sure to check in at the gate before sunset.
You are welcome to attend EAAA meetings in room 1704 at Pensacola State College at 7 p.m. on these Fridays; January 5, February 3, and March 3.
For more information on the Escambia Amateur Astronomers and our local star gazes for the public, visit our website or call our sponsor, astronomy teacher Lauren Rogers at Pensacola State College; email her at lrogers@pensacolastate.edu. Join us on Facebook. If you want free solar filters for sunspot viewing and the April 8, 2024 solar eclipse, drop a line to Dr. Wayne Wooten on the FB page with your address, or call him at (850) 281-9334, or email him at johnwaynewooten@gmail.com.
