Astronomy
Observing
What to look at, and when, from the UK.
The Moon
The Moon is the perfect first target. Surprisingly, full Moon is not the best time to look: the most dramatic views come along the terminator, the line between day and night, where shadows make craters and mountains stand out. Around first quarter is ideal.
The planets
Through a small telescope, Jupiter shows its cloud belts and four bright moons, whose positions change from night to night. Saturn's rings are an unforgettable sight. Venus shows phases like the Moon, and Mars reveals surface markings when it is close to Earth. Planets move across the sky over the year, so check an app to see which are visible.
Stars
Stars come in different colours, which are easiest to see in binoculars or a telescope. Double stars are rewarding targets: Albireo in Cygnus shows a lovely gold and blue pair, and Mizar in the handle of the Plough has a naked-eye companion, Alcor.
Deep-sky objects
Star clusters, nebulae and galaxies are faint, so they are best seen from a dark site on a moonless night. Some favourites are:
- The Orion Nebula (M42), a glowing cloud where new stars are forming.
- The Pleiades (M45), a beautiful star cluster that looks superb in binoculars.
- The Andromeda Galaxy (M31), our nearest large neighbouring galaxy.
- The Great Hercules Cluster (M13), a ball of hundreds of thousands of stars.
- The Double Cluster in Perseus, two star clusters side by side.
Seasonal highlights
Winter
Orion and the Orion Nebula, Taurus with the Pleiades and Hyades, and long, dark nights.
Spring
Leo, the Plough high overhead and, with a telescope, galaxies in Leo and Virgo.
Summer
The Summer Triangle, Albireo and M13. Nights are short and never fully dark around midsummer.
Autumn
The Andromeda Galaxy, the Double Cluster and Cassiopeia as the dark evenings return.
Observing tips for the UK
- Check a cloud forecast such as Clear Outside before you set up.
- Put your telescope outside for a while before observing so it cools to the air temperature and gives sharper views.
- Get away from street lights if you can, and let your eyes adapt to the dark.
- Dress warmly, even in summer, and keep a red torch handy.
- Plan around the Moon: a bright Moon washes out faint galaxies and nebulae.
Solar safety: never point binoculars, a telescope or a camera at the Sun without a proper, certified solar filter fitted securely over the front. Permanent eye damage can happen instantly.