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FRIDAY, JANUARY 23
■ Look west-southwest early this evening. Oops, the Moon dropped Saturn!
But when will Saturn be straight below the Moon for you, making the illusion complete? That will depend on your location. The exact time will be hard to judge — because the whole scene below will slightly tilt to the right as it descends westward, while the Moon slowly travels toward upper left along its orbit. The two effects will more or less cancel out.
■ After dark this week, spot the bright, equilateral Winter Triangle in the southeast. Sirius is its lowest and brightest star. Betelgeuse stands above Sirius by about two fists at arm's length. Left of their midpoint shines Procyon.
Can you discern their colors? Sirius (spectral type A0) is cold white, Betelgeuse (M2) is yellowish orange, and Procyon (F5) is a pale, very slightly yellowish white.
And, standing 4° above Procyon is 3rd-magnitude Gomeisa, Beta Canis Minoris, the only other easy naked-eye star of Canis Minor. Its name is from the ancient Arabic for "little bleary-eyed one."
SATURDAY, JANUARY 24
■ In early evening, the enormous Andromeda-Pegasus complex runs from very high in the west down to low in the west.
Face west after nightfall and look straight up. Perseus is crossing the zenith. A fist of so west of there, spot Andromeda's high foot: 2nd-magnitude Gamma Andromedae (Almach), slightly orange. Andromeda is standing on her head, which is also the top corner of the Great Square of Pegasus.
Down from the Square's bottom corner run the stars profiling the back of Pegasus's neck and head, ending with a rightward jag to his nose: 2nd-magnitude Enif, due west. It too is slightly orange.
That bright point off to the lower left of the Great Square is Saturn.
SUNDAY, JANUARY 25
■ First-quarter Moon (exact at 11:47 p.m. EST). The Moon shines in Aries this evening. Spot Alpha Arietis and dimmer Beta Arietis a few degrees to the Moon's upper right, one above the other. They're 2nd and 3rd magnitude, respectively.
■ Closer to the lower left of Beta Arietis, by a finger-width at arm's length, is 4th-magnitude Gamma. This is a lovely telescopic double star, waiting right there for you when you have your telescope out for the Moon tonight. Both components are magnitude 4.6 and white. They're lined up almost precisely north-south, 7.4 arcseconds apart.
The pair is 165 light years away, and each star is 42 times as luminous as the Sun. They're at least 370 a.u. apart, which is at least 12 times the distance of Neptune from the Sun.
■ On the half-lit Moon itself, your scope will show the sunrise terminator beginning to unveil Mare Imbrium in the lunar north. The Alps and Apennine mountain ranges outline Imbrium's early sunlit rim standing out in stark, long-shadowed relief. Cupped inside them are the smallish craters Aristillus and Autolycus, almost exactly on the terminator's edge for evening hours in the Americas.
The terminator from the center of the lunar disk southward crosses the rugged, heavily cratered Southern Highlands.
Barely beyond the dark edge of the terminator, find some tiny, starlike speck of a peak catching the very first rays of the sun. How soon during your observing session can you see it visibly growing?
MONDAY, JANUARY 26
■ Orion is high in the southeast right after dark and stands highest due south around 8 or 9 p.m. Orion is the brightest of the 88 constellations, famously recognizable even through bright moonlight or heavy city light pollution.
If you know where to look. Right after nightfall this evening, find Orion lower right of the Moon by about two fists at arm's length. Around about 8 p.m. Orion stands straight under the Moon.
Whenever Orion stands more or less upright, such as on midwinter evenings, his three-star belt is diagonal.
TUESDAY, JANUARY 27
■ The gibbous Moon shines near the Pleiades tonight, as shown below. Cover the Moon with the edge of your hand to help reveal the Pleiades to its right.
North Americans can watch the Moon move farther away from the Pleiades during the course of the evening. It occulted some of them in daylight. But Europeans will have seen see some of these occultations in darkness, with the stars disappearing on the Moon's dark limb. Details.
WEDNESDAY, JANUARY 28
■ Now the Moon is much farther from them Pleiades than last night but almost same distance from Aldebaran as it was then, as shown above.
THURSDAY, JANUARY 29
■ The Moon this evening forms a nearly isosceles triangle with the horntips of Taurus, Beta and lesser Zeta Tauri, glimmering to its right. The Moon is about 9° from each (for evening in the Americas).
Bright Jupiter shines farther to the Moon's lower left in early evening, then straight left of it by about 10 or 11 p.m. Judge "straight left" for something so near the zenith by standing and facing it directly.
FRIDAY, JANUARY 30
■ The gibbous Moon shines right amidst Jupiter, Pollux, and Castor tonight. That's their brightness order, fr0m brightest to faintest.
Can you get a photo that shows them all well despite their vast brightness differences? Your trouble doing this will demonstrate what a wide dynamic range the human retina has, without our being aware of it.
■ Through the moonlight after nightfall the Great Square of Pegasus is sinking in the west, tipped onto one corner with brighter Saturn glowing to its lower left. Meanwhile the Big Dipper is creeping up in the north-northeast, tipping up on its handle.
SATURDAY, JANUARY 31
■ Now the Moon shines lower left of Jupiter, Pollux, and Castor at dusk. It's directly left of them high in late evening.
SUNDAY, FEBRUARY 1
■ Full Moon. It's exactly full at 5:09 p.m. EST, so it rises almost exactly at sunset (for North America). And for all practical purposes it comes up precisely opposite the Sun's location on the horizon.
Full darkness will reveal that the Moon is upper right (west) of the Sickle of Leo. By midnight the scene has rotated so the Moon is directly right of the Sickle.
■ Algol should be at its minimum brightness, magnitude 3.4 instead of its usual 2.1, for a couple hours centered on 7:36 p.m. EST. It takes several more hours to fully rebrighten.
Mercury, Venus, and Mars all remain out of sight behind the glare of the Sun.
Jupiter (magnitude –2.6) shines in the Pollux stick figure of the Gemini twins. It's only a little past its January 9th opposition, so it shines in the east during dusk, the first "star" to show through the fading twilight. It dominates the high east after dark, then the high southeast. Castor and Pollux shine nearby. Jupiter this week remains within 1½° of Delta Geminorum, magnitude 3.5, almost 300 times fainter.
Jupiter is highest in the south and thus telescopically sharpest by 10 or 11 p.m. It's a big 46 arcseconds wide. See "Jupiter Rules!" in the January Sky & Telescope, page 48, which includes a map of its dark belts and bright zones.
Jupiter about as it looks visually in a 6- or 8-inch telescope at very high power on a night of good seeing. Tim Dearing of the Louisville Astronomical Society took this shot with an iPhone through the eyepiece of an 8-inch Dobsonian telescope in early 2021. It records the Jovian moon at left casting its tiny shadow onto the planet's cloudtops near the lower left limb.
Jeff Phillips of Eugene, Oregon, took this image of Jupiter with Ganymede and its shadow in transit at 6:42 UT January 14th. Ganymede is mottled gray; its shadow is black. North is up. Phillips used a Celestron 14-inch Schmidt-Cassegrain telescope and a ZWO ADC and ZWO ASI676 camera. He writes, "Even though the temperature was below freezing, the Clear Sky Chart forecast for the Ganymede transit called for good to excellent seeing. I was able to capture a dozen 3-minute videos. The best four stacks were sharpened and combined with WinJupos. This picture is based on the best 25% of 100,000 video frames!"
Saturn (magnitude +1.1, at the Aquarius-Pisces border) is the brightest dot in the southwest at nightfall, lower left of the Great Square of Pegasus. It descends through the evening and sets in the west around 9 p.m.
In a telescope Saturn's rings are still very thin but gradually opening up. They're now tilted 2° to our line of sight. The rings' thin black shadow on Saturn's globe is slowly widening too.
Saturn as it looked visually at very high power in a small scope a season ago, when the rings were last tilted by 2.0°. Imager AstroCreo aimed a cellphone through the eyepiece of a 70-mm alt-azimuth refractor for this shot on Saturn's opposition night, September 21-22. Three of its moons join in: from upper right, Titan, Tethys, and Dione. (The faint parts here are somewhat brightness-enhanced.)
Saturn imaged by Christopher Go on November 29th when the ring inclination was very close to minimum, a super-thin 0.4°. North is up. Now the ring tilt is widening, and the rings' shadow on the globe is widening too. Rhea and smaller Tethys are nearly in conjunction just off the east (left) end of the rings.
Uranus (magnitude 5.6, in Taurus 5° south of the Pleiades) is very high in the south these evenings. At high power in a telescope it's a tiny but non-stellar dot, 3.8 arcseconds wide. You'll need a detailed finder chart to identify it among similar-looking faint stars, such as the chart in the November Sky & Telescope, page 49.
Neptune is a telescopic "star" of magnitude 7.9, a dim speck just 2.3 arcseconds wide 2° from Saturn. For Neptune you'll need an even more detailed finder chart.
All descriptions that relate to your horizon — including the words up, down, right, and left — are written for the world's mid-northern latitudes. Descriptions and graphics that also depend on longitude (mainly Moon positions) are for North America. Eastern Standard Time (EST) is Universal Time minus 5 hours. UT is also known as UTC, GMT, or Z time.
Want to become a better astronomer? Learn your way around the constellations. They're the key to locating everything fainter and deeper to hunt with binoculars or a telescope.
This is an outdoor nature hobby. For a more detailed constellation guide covering the whole evening sky, use the big monthly map in the center of each issue of Sky & Telescope, the essential magazine of astronomy.
For the attitude every amateur astronomer needs, read Jennifer Willis's Modest Expectations Give Rise to Delight.
Once you get a telescope, to put it to good use you'll want a much more detailed, large-scale sky atlas (set of charts). The basic standard is the Pocket Sky Atlas, in either the original or Jumbo Edition. Both show all 30,000 stars to magnitude 7.6, and 1,500 deep-sky targets — star clusters, nebulae, and galaxies — to search out among them.
The Pocket Sky Atlas plots 30,796 stars to magnitude 7.6, and hundreds of telescopic galaxies, star clusters, and nebulae among them. Shown here is the Jumbo Edition, which is in hard covers and enlarged for easier reading in the dark by red flashlight. Sample charts. More about the current editions.
Next up is the larger and deeper Sky Atlas 2000.0, plotting stars to magnitude 8.5; nearly three times as many, as well as many more deep-sky objects. It's currently out of print, but maybe you can find one used.
The next up, once you know your way around well, are the even larger Interstellarum Deep-Sky Atlas (with 201,000+ stars to magnitude 9.5 and 14,000 deep-sky objects selected to be detectable by eye in very large amateur telescopes), and Uranometria 2000.0 (332,000 stars to mag 9.75, and 10,300 deep-sky objects).
Read How to Use a Star Chart with a Telescope. It applies just as much to electronic charts on your phone or tablet — which many observers find handier and more versatile, if perhaps less well designed, than charts on paper.
You'll also want a good deep-sky guidebook. A beloved old classic is the three-volume Burnham's Celestial Handbook. It was my bedside reading for years. An impressive more modern one is the big Night Sky Observer's Guide set (2+ volumes) by Kepple and Sanner. The pinnacle for total astro-geeks is the new Annals of the Deep Sky series, currently at 11 volumes as it works its way forward through the constellations alphabetically. So far it's up to H.
Can computerized telescopes replace charts? Well, I used to say this:
"Not for beginners, I don't think, unless you prefer spending your time getting finicky technology to work rather than learning how to explore through the sky yourself. As Terence Dickinson and Alan Dyer say in their Backyard Astronomer's Guide, 'A full appreciation of the universe cannot come without developing the skills to find things in the sky and understanding how the sky works. This knowledge comes only by spending time under the stars with star maps in hand and a curious mind.' Without these, 'the sky never becomes a friendly place.' "
Well, things change. The technology has continued to improve and become more user-friendly — particularly with software that can now recognize any star field to determine exactly where the telescope is pointed — finally bypassing all aiming imperfections in the mount, tripod, gears, bearings and other mechanics, or in the user's skill in setting up.
The latest revolution is the rise of small, imaging-only "smartscopes." These take advantage of not only today's pointing technology, but also the vastly better capabilities of imaging chips and processing compared to the human retina and visual cortex. The most sophisticated image stacking and processing can also come built in. The result is decent deep-sky imaging from shockingly small, low-priced units. The image may be viewable on your phone or computer as it builds up in real time. Small smartscopes can enable direct contributions to citizen-science projects.
These are changing the hobby at the entry level. For more on this revolution see Richard Wright's "The Rise of the Smart Telescopes" in the November 2025 Sky & Telescope. And read the magazine's review of this especially small one.
If you get a larger, more conventional computerized scope that allows direct visual use, make sure that its drives can be disengaged so you can swing it around and point it readily by hand when you want to, rather than only slowly by the electric motors (which eat batteries).
Audio sky tour. Out under the evening sky with your
earbuds in place, listen to Kelly Beatty's monthly
podcast tour of the naked-eye heavens above. It's free.
"The dangers of not thinking clearly are much greater now than ever before. It's not that there's something new in our way of thinking, it's that credulous and confused thinking can be much more lethal in ways it was never before."
— Carl Sagan, 1996
"Facts are stubborn things; and whatever may be our wishes, our inclinations, or the dictates of our passion, they cannot alter the state of facts and evidence."
— John Adams, 1770
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