What can you see in the night sky without a telescope?

Quite a lot. Without any optics you can see the Moon in detail, five planets, thousands of stars, the International Space Station and other satellites, meteors and, from a properly dark place, the band of the Milky Way.

I build Sky Map, the app mentioned below, so weigh my suggestions with that in mind.

What the naked eye shows

• The Moon. Dark “seas”, bright highlands and, near the edge between light and shadow, a rough line where craters catch the sunlight.
• Planets. Mercury, Venus, Mars, Jupiter and Saturn are all visible without help. They tend to shine steadily while stars twinkle, and they sit near the path the Sun and Moon follow.
• Bright stars and constellations. Even from a suburb you can trace Orion, the Big Dipper or Cassiopeia.
• Star clusters. The Pleiades look like a tiny, misty dipper.
• Satellites and meteors. A steady dot crossing the sky in a few minutes is usually a satellite. A streak lasting a second is a meteor.
• The Milky Way and the Andromeda Galaxy. Both need a dark site away from city lights and a moonless night.

How to see more

Give your eyes time. Full dark adaptation takes around 20 to 30 minutes, and one glance at a bright screen resets part of it. Turn your screen brightness down and look slightly to the side of a faint object, because the edge of your vision is more sensitive in the dark.

Pick the night as well as the place. A bright Moon washes out faint objects, and thin cloud or haze hides more than you would expect.

Where an app helps

Sky Map shows stars, planets, constellations and satellites over the camera view when you point your iPhone at the sky. The planet visibility timeline tells you which planets are up and when, the astronomical calendar lists meteor showers and eclipses, and Tonight’s Sky Conditions shows cloud cover, humidity and the best time to look. The core sky map works without internet. Sky Map is free to download, the AR view is free, and some features are paid.

An app cannot make faint things brighter. It tells you where to look, then your eyes do the rest.

Read next: what planets are visible tonight, dark adaptation with a phone in hand and stargazing in the city.