Binocular tour

Discover summer’s most spectacular wide-field sights, including open cluster M11

1. The Scutum Star Cloud

We’ll begin with the astonishingly rich star field in the northeast quarter of Scutum. It’s so easy to find that it has been mistaken for a real cloud on a clear night. Look for the ripples of stars, formed by the indistinct dark nebulae that weave among them. You should also see the even richer condensation of nearly 3,000 hot blue stars that forms the densest of all open clusters, M11, the Wild Duck Cluster.  SEEN IT

2. The Swan Nebula M17

Next, identify Gamma (γ) Scuti and pan 2.5˚ to the southwest, where you will find a misty patch that Charles Messier described as, “A train of light without stars, in the shape of a spindle, of 5 or 6 minutes in extent.” Keep it centred while you use averted vision to reveal a small hook-like extension extending south from the top right-hand side of the patch, like an inverted tick.  SEEN IT

3. The Sagittarius Star Cloud

M24 lies a bit more than halfway from Gamma (γ) Scuti to Mu (μ) Sagittarii. It is another bright patch of light that is easily mistaken for a cloud just above the horizon. It is part of the Sagittarius Arm of the Milky Way that is partly obscured by dust. Easily the richest vista visible in 10x50s, it has around 1,000 stars that can be resolved in a single field of view.  SEEN IT

4. M22

Find Kaus Boralis (Lambda (λ) Sgr), the ‘peak’ of Sagittarius’s Teapot asterism, and put it at four o’clock in the field of view. M22, the largest globular cluster visible from the UK, should be obvious near the centre. This beautiful object shows a much brighter core, very much like the coma of a comet, making it clear why Charles Messier included it in his catalogue of objects that were not to be mistaken for comets.  SEEN IT

5. 52 and 53 Sagittarii

Our next targets are easy pairs of double stars. The first is the white pair, 52 (mag. +4.6) and 51 (mag. +5.6) Sagittarii, which are 13 arcminutes apart. One is slightly bluer than the other – can you tell which? 53 Sgr shines at mag. +6.3, a third of a magnitude fainter than its orange companion, 4 arcminutes to the east. Both are line-of-sight associations and not true binary stars.  SEEN IT

6. Jupiter

You won’t see Jupiter’s surface detail in small binoculars, but it’s easy to watch the stately dance of its Galilean moons. The dazzling planet can impair the view, so ensure your optics are clean and focused. Start with Ganymede and Callisto, and use the chart on page 45 to find when they are at greatest elongation and furthest from Jupiter’s glare.  SEEN IT

✓ Tick the box when you’ve seen each one