Binocular tour

Locate wide-field wonders, including two parallelograms in Pisces and Capricornus

1. Jupiter’s and Saturn’s moons

10x Start by finding the ‘sweet spot’ 50 in your field of view where the binoculars’ chromatic aberration partly counteracts atmospheric dispersion and Jupiter’s colour-fringing is minimal. Don’t expect to see planetary detail with 10x50 binoculars, but you can plot the night-tonight dances of the gas giants’ moons. Jupiter’s Galilean moons and Saturn’s brightest moon, Titan, are easy to spot when they are separated from the planet

by more than an arcminute.  SEEN IT 2. Capricorn’s rhombus, kite and parallelogram

One way of remembering star 10x 50 patterns in different regions of the sky is to use familiar shapes as aidemémoires. Delta (δ) Capricorni is common to three quadrilateral asterisms. It makes a rhombus with Mu (μ)), Lambda (λ)) and 42 Capricorni; a kite if we include 46 Capricorni instead of λ; and a parallelogram with

Nashira (Gamma (γ)), Epsilon (ε) and Kappa (κ) Capricorni. What other shapes can you find in this region of sky?  SEEN IT

3. Psi Aquarii star field

10x This star field contains stars of the 50 main spectral classes except O, so you can use it to get a sense for the colours of each. Psi2 (ψ2) Aquarii is B, Psi3

(ψ3) Aquarii is A, 96 Aquarii is F, 94 Aquarii is G, Psi1 (ψ1) Aquarii is K, and Chi (χ) Aquarii and Phi (φ) Aquarii are both M.

Also seek Neptune, which is 2° east of 96 Aquarii and is easy to view in binoculars, if you know where to look.  SEEN IT

4. TX Piscium

The easternmost star in the southern 10x 50 circlet of Pisces is one of the reddest in the sky, the variable (mag. +4.8 to +5.2) TX Piscium. This ruby droplet is a carbon star: it pulsates in size, brightening as it expands, then throws off layers of soot as it contracts, making it dim.  SEEN IT 5. The Pisces parallelogram

10x 7.5° southeast of TX Pisces we find 50 another quadrilateral asterism. This 3° x 1° parallelogram has 27, 29, 30 and 33 Piscium at its corners. The northeast corner is blue-white 29 Piscium, and diagonally opposite is orange 30 Piscium. The other two corners appear yellowish. At first glance, the parallelogram seems to be empty: it contains only one star brighter than 8th magnitude.  SEEN IT

6. The Helix Nebula, NGC 7293

You’ll need a good southern horizon, 15x 70 along with a transparent sky and full dark-adaptation, if you want to observe this planetary nebula. Use the chart to identify Upsilon (υ) Aquarii and 47 Aquarii. About a third of the way from Upsilon Aquarii to 47 Aquarii you’ll find a faint circular patch about 10 arcminutes in diameter.  SEEN IT

✓

Tick the box when you’ve seen each one