Maybe you just got a shiny new telescope to call your own. Congratulations — you could be on your way to making lifelong friends with stupendous, faraway things up there in the dark over your roof every night, things you never knew were floating there above you.
However, most of them are so far and faint that just finding and positively identifying them is the challenge — and the accomplishment! Whether your new scope is a long, sleek tube or a compact marvel of computerized wizardry, surely you're itching to try it out.
Before You Observe
Here are three essential tips for starting on the right foot, to avoid frustrations and move quickly up the learning curve.
First, get your scope all set up indoors. Read the instructions, and get to know how everything works — how the telescope moves around, how to change eyepieces, and so on — in warmth and comfort. That way you won't have to figure out unfamiliar knobs, settings, and adjustments outside in the cold and dark.
Second, take the scope outside in the daytime and familiarize yourself with how it works on distant scenes — treetops, buildings — to get a good feel for what it actually does. Don't be surprised if the view is upside down; allowing this keeps the optical parts nice and simple, and it doesn't matter because there's no up or down in space.
You'll quickly find that a telescope's lowest magnification (the eyepiece with the longest focal length, meaning the one with the highest number printed on it) gives the brightest, sharpest, and widest views, with the least amount of the wiggles. The lowest power also makes it easiest to find what you're trying to aim at, thanks to that relatively wide field of view. So, you'll always want to start off with the lowest power. Switch to a higher-magnification eyepiece only after you've found your target, got it centered, and had a good, careful first look.
Also: If the telescope has a little finderscope or a red-dot pointing device attached to its side, daytime is the easiest time to align the finder with the main scope. You really need to do this. Aim the telescope at a distant treetop or other landmark and center it in the main view. Lock the mount's motions if the mount allows this. Recheck that the treetop is still centered, and then look through the finderscope. Use the finder's adjustment screws on the sides to center the crosshairs (or red dot) on the same treetop. Then recheck again that it's still in the center of the main scope's view, in case you may have bumped it off in the process.
Third, plan to be patient. Spend time with each sky object you're able to locate, and really get to know it. Too many first-time telescope users expect something like Hubble-like brightness and color in the eyepiece — when in fact most astronomical objects are very dim to the human eye. Moreover, our night vision sees dim things mostly as shades of gray, not in color. Much of what the universe has to offer is subtle and, again, extremely far away!
But the longer and more carefully you examine something, the more of it you'll gradually discern. Astronomy teaches patience.
On the other hand, the Moon and the naked-eye planets are bright and easy to find! They make excellent first targets for new telescopic observers. Sky & Telescope's This Week's Sky at a Glance has suggestions for both telescopic and naked-eye viewing of the brightest stars and planets.
Here are some suggestions for starting off.
New-Telescope Delight: The Moon
The Moon is one celestial object that never fails to impress in even the most humble scope. It’s our nearest neighbor in space — big, bright, starkly bleak, and just a quarter million miles away. That's a hundred times closer than the nearest planet ever gets. An amateur telescope and a detailed Moon map can keep you busy forever.
Tonight (December 25, 2023) the Moon is almost full, and it's exactly full tomorrow night. But full phase is actually the worst time to see detail on the Moon! That's because its whole face is brighly sunlit by the Sun directly behind us, so the lunar mountains, hills, craters and cliffs will cast no shadows to reveal them as other than flat. Everything will just be shades of brilliant gray-white. Do have a look, though. The grayer areas are the lunar plains or "seas"; the maria in Latin. Brighter areas are more mountainous, and many craters large and small will reveal themselves by their bright white rims.
You see lunar surface features best when they are near the Moon's terminator, the lunar sunrise or sunset line. For instance, look at the photo at the top of this page. The terminator is where the low Sun in the Moon's sky makes even low landforms cast stark black shadows.
The advancing terminator unveils new landscapes day by day when the Moon is waxing, then hides them in darkness day by day when the Moon is waning after full. In between at full Moon, the terminator lies all around the Moon's edge essentially out of sight.
So be patient. The Moon will next be waxing in the evening sky, beautifully rich in a telescope, starting around January 13th or 14th. On the 16th, it will show the same phase as the photo above.
Now some good luck. Giant Jupiter await you as the brightest point of light in the evening sky. Step outside in early evening, face more or less south, look way high, and there it is: a bright white dot outshining any star.
Even the smallest telescope at low power will show Jupiter's four pointlike moons on either side of it. They change configuration endlessly from night to night. Tonight, December 25th, you'll find Io and Europa on one side of Jupiter, Callisto closer in, and Ganymede farther out on the other side. Tomorrow their configuration will be quite different, and on and on while Jupiter is in view all winter. They've been at it up there every night for 4.6 billion years, ever since the solar system formed.
Now switch to fairly high power. Jupiter itself spins so fast (once every 10 hours) that it's not quite round, as a small scope will reveal.
And can you make out any of Jupiter's parallel cloud belts? They darken or brighten, broaden or narrow, over a matter of months or years. They won't exactly leap out at you. Keep looking, and looking. Carefully. You may catch an occasional moment of steady air when the planet sharpens up. The "atmospheric seeing," as it's called, changes from blurrier to sharper from night to night and often from moment to moment.
There's another reason to keep looking. When you're working near the limit of your vision, as you usually will be in astronomy, it takes time and continued attention to see all that you can see. Things that were at first invisible may start to occasionally flicker into view, then become definite enough to hold almost steadily. Did we say astronomy teaches patience?
Jupiter's famous Great Red Spot, in the edge of the South Equatorial Belt, is a harder catch. It may need at least a 6-inch scope and a night of especially steady seeing. The Red Spot is currently very pale orange (it too changes), and it has been gradually shrinking for years. And, of course, it has to be on the side of Jupiter facing us at the time when you look! Which is only half the time.
Saturn too is now in early-evening view. Hold your fist out at arm's length, and count about six fist-widths to Jupiter's lower right (depending a bit on the size of your hand and the length of your arm). Around there will be a steady-glowing little dot, quite a bit dimmer than Jupiter and just a trace yellowish. Don't confuse it with the similarly bright star Fomalhaut, which is about two fists to Saturn's lower left.
Even a small telescope at fairly high power will reveal the planet's iconic rings. Yes, Saturn actually does look like that! But Saturn is getting lower now, and low mean poor telescopic seeing. So get your scope on it as early in the evening as you can.
Saturn too has multiple moons for amateur telescopes, though they're much fainter than Jupiter's. The brightest is Titan. Tonight it's off to one side by almost five times the width of Saturn's rings, and nearly in line with them. See if you can make out its slightly orange tint.
The other bright planets? Venus is the bright "Morning Star" in early dawn rather low in the southeast. In a telescope it's currently the shape of a tiny gibbous Moon, dazzlingly white. During the second week of January, look for little Mercury about a fist to the lower left of Venus. Mars is currently out of sight behind the glare of the Sun and will remain so for months to come.
More New-Telescope Sights
Of course there's much more to the night sky than the Moon and planets! Winter nights often bring crisp, transparent skies with a grand canopy of stars. But with so many inviting targets overhead, where to point first?
Well, off to the left of Jupiter by two or three fists is the Pleiades star cluster. It's visible to the naked eye as a little patch about the size of your fingertip at arm's length. Tonight (December 25th) the Pleiades are about midway between Jupiter and the Moon. Moonlight in the sky washes out the view of faint sights, but even so you shouldn't have too much trouble with the Pleiades. By December 28th or 29th the Moon will be gone from the early-evening sky, leaving the sky nice and dark.
Most people can make out the six brightest Pleiades stars with the unaided eye. They form a tiny dipper shape. But a telescope will show a whole swarm, and the dipper pattern will look huge and bright — even overspilling your eyepiece view at all but the very lowest magnification.
Astronomers have determined that the Pleiades cluster has more than 500 stars in all. Like other star clusters, the Pleiades are held together by their mutual gravity. This one is classed as an open cluster for the stars' relatively uncrowded arrangement. It's nearby as star clusters go, traveling through space as a swarm about 440 light-years away.
The Pleiades stars, astronomers have determined, began to shine only about 80 million years ago. This makes them mere toddlers compared to our Sun and solar system, age 4.6 billion years. These youthful suns are astonishingly energetic. Alcyone (al-SIGH-oh-nee), the brightest, is at least 350 times as luminous as our Sun. Like the other bright Pleiads it gleams with an intense bluish-white light — a sign that it’s unusually hot and massive.
Next, here's a deeper suggestion. The familiar constellation Orion climbs the southeastern sky in the evening at this time of year. In its middle, look for the three-star line of Orion's Belt. The Belt is almost vertical as it rises in early evening. It turns diagonal (as shown below) later at night.
Just a few degrees south of the Belt, in other words a few finger-widths at arm's length, runs a smaller, dimmer line of stars: Orion's Sword. Within it lies the Orion Nebula, a luminous cloud of gas and dust where new stars are forming by the hundreds. It shows pink in many photographs, but to the human eye it's dim gray with a hint of green. The nebula is evident in any telescope once you get pointed at it, and so is the tight quartet of young stars near its center, known as the Trapezium. Astronomers refer to the Orion Nebula as Messier 42 (M42), and you'll see it labeled that way on star charts. Located about 1,400 light-years away, it's the closest massive star-forming nebula to Earth.
Dim objects like nebulae are best seen when the sky is moonless and really dark. The farther you can get out from under the skyglow of city light pollution, the better. But don't let light pollution dissuade you from finding what you can see from your own backyard or apartment balcony! Choose reasonably bright targets to hunt, and develop the skills to find them and observe them carefully so you'll be ready to make the most of better conditions when the chance arises. For instance, the sky may be especially clean and dark the night after a storm passes through.
You can use Orion's Belt as a pointer to other things. Extend its line far upward across the sky, by about two fist-widths at arm's length, and there's the relatively bright star Aldebaran, the orange eye of Taurus. Continue on by about another fist and you'll reach the Pleiades.
Next Steps in Astronomy
To find much else in the night sky, start learning the constellations. They're the key to locating everything fainter and deeper to hunt with binoculars or a telescope — the same way that on a globe of Earth you need to know the continents and countries before you can pinpoint, say, Milan or Sydney or Jakarta.
For an easy-to-use 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 (ahem).
You'll also want a good, detailed star atlas (set of more detailed maps), such as the widely used Pocket Sky Atlas; a good deep-sky guidebook; and some practice in how to use the maps to pinpoint the aim of your telescope onto something too faint to see with your eyes alone. So be sure to read our article How To Use a Star Chart with a Telescope.
Whatever else, stick with it. Nobody is born knowing this stuff. Work your way into the hobby at your own pace, finding things to know and do and understand without worrying about everything else you haven't got to yet. That's really what life in a big universe is all about, right?