Pick your night
The single most important thing is a clear sky. Thin high cloud that barely registers in daylight can hide every star fainter than the brightest few, so check a forecast that shows cloud cover by the hour, not just a sun or rain icon.
Next, the Moon. A bright Moon is lovely to look at, but it floods the sky with light and hides faint objects. For your first night, a crescent or no Moon at all is ideal; if the Moon is near full, plan to look at the Moon itself and the bright stars and planets. The Moon phase calendar shows which nights are darkest this month.
Finally, timing. The sky isn’t fully dark until the Sun is 18° below the horizon, which takes from about an hour and a quarter after sunset near the equator to two hours or more at high latitudes in summer. You can start earlier, while the brightest stars and planets appear one by one in twilight; that’s actually the easiest way to learn them, because only the brightest are showing.
What to bring
- More warm clothing than you think. Standing still at night is cold, even in summer. A hat and a blanket make the difference between ten minutes and an hour.
- Something to sit or lie on. A reclining chair is the most underrated piece of astronomy equipment. Craning your neck is tiring, and comfortable observers see more.
- A dim red light. A red bicycle light or a flashlight covered with red cellophane lets you see where you’re walking without ruining your night vision.
- Your phone, turned right down. Use a red or night mode and the lowest brightness. One look at a full-brightness screen undoes minutes of adaptation.
- Binoculars, if you have them. Any pair will do. They’re not required for this guide, but they turn many fuzzy patches into clusters of stars. See binoculars or telescope for what to expect.
Give your eyes time
When you first step outside you’ll see a handful of stars. Wait. Over the next 20 to 30 minutes your eyes become dramatically more sensitive, and the sky fills in. This is dark adaptation, and it is easily undone by bright light, which is why the red light matters.
There’s more on this, and on light pollution, in dark adaptation and light pollution.
Find your way with signposts
Don’t try to learn all 88 constellations. Learn a few bright, distinctive patterns and use them to point to everything else. Which ones you can see depends on your latitude and the season, but from mid-northern latitudes these three cover the whole year.
The Big Dipper and Polaris
The Big Dipper, seven bright stars in the shape of a ladle, is part of Ursa Major. From most of the US, Canada and Europe it never sets. The two stars at the end of the bowl, Merak and Dubhe, are the pointers: follow the line from Merak through Dubhe about five times their separation and you reach Polaris, the North Star. It isn’t especially bright, but it marks north almost exactly and barely moves all night.
Now follow the curve of the Dipper’s handle away from the bowl. Keep going along the same arc and you reach Arcturus, a bright orange star. Astronomers remember it as “arc to Arcturus,” and on spring evenings you can “speed on to Spica,” a bluish star farther along the same curve.
Cassiopeia
On the far side of Polaris from the Big Dipper sits Cassiopeia, five stars in a W or M shape. When the Dipper is low on autumn evenings, Cassiopeia is high, so between them one is always well placed. Cassiopeia points toward the Double Cluster in Perseus and the Andromeda Galaxy.
Orion
From late fall to early spring, Orion dominates the evening sky: a large rectangle of bright stars with three in a straight line across the middle, his belt. Red Betelgeuse marks one shoulder and blue-white Rigel the opposite knee. Follow the belt down and to the left to Sirius, the brightest star in the night sky. Follow it up and to the right to orange Aldebaran, and a little beyond to the Pleiades.
On summer evenings, Orion is gone and the Summer Triangle takes over: Vega, Deneb and Altair, three bright stars high overhead, with the Milky Way running through the middle if your sky is dark enough.
Measure the sky with your hand
Star charts and apps describe distances in degrees. Your hand, held at arm’s length, is a surprisingly consistent ruler for this, because people with bigger hands tend to have longer arms.
| At arm’s length | Covers about | For example |
|---|---|---|
| Little finger | 1° | Twice the width of the full Moon |
| Three middle fingers | 5° | The gap between the Dipper’s pointer stars |
| Closed fist | 10° | Height of a planet that is “10° up” |
| Spread hand, thumb to little finger | 20–25° | Length of the Big Dipper |
From the horizon to the point straight overhead is 90°, about nine fists. When SkyMate or a chart says something is 30° up in the southeast, face southeast and stack three fists from the horizon.
What to look at first
These targets are bright, easy to find and rewarding even from a suburb. Check which are above the horizon on Tonight.
| Target | With | What you’ll see |
|---|---|---|
| The Moon | Eyes or binoculars | Craters along the line between light and shadow |
| A bright planet | Eyes, then binoculars | A steady, bright point; Jupiter shows up to four moons |
| Pleiades | Eyes or binoculars | A tiny dipper of blue-white stars |
| Orion Nebula | Binoculars | A glowing mist in Orion’s sword |
| Double Cluster | Binoculars | Two rich star clusters side by side |
| Albireo | Small telescope | A gold and blue double star |
Planets are easier than you might expect; how to find planets explains how to tell them from stars.
Keep going
Go out again within a week, while the same stars are in the same places at the same time. Find the patterns you learned, then add one new constellation next to them. Within a month you’ll be able to find your way around most of the sky you can see from home.
If something you were told to look for didn’t show up, it probably wasn’t you. Why can’t I see it? explains the difference between an object being up and being visible.