On the UK night of 6—7 July 2017, three weeks after the opposition of Saturn in the constellation of Ophiuchus, the ringed planet can be identified as the magnitude-zero ‘star’ highest in the southern UK sky around 11:40pm BST. As seen from the heart of the British Isles at this time, Saturn struggles to attain a peak altitude of just 14 degrees, or three-quarters of the span of an outstretched hand held at arm’s length above the horizon.
While there is a slim chance that you can confuse Saturn with first-magnitude Antares in the constellation of Scorpius that lies 14 degrees (or one-and-a-half spans of a fist held at arm’s length) to the right of the planet, the supergiant star is the fainter of the two and has a reddish-orange hue in binoculars and small telescopes.Returning to Saturn in a small telescope, the UK night of 6—7 July is ideal for spotting the ringed planet’s largest moon, Titan. This cloud-covered world some 3,200 miles in diameter looks just like a magnitude +9 star close to its greatest westerly elongation from Saturn, some 4½ ring diameters away. Titan orbits its parent planet every 16 days, so expect to see it a similar distance to the east of Saturn on 14 July.
By convention, mountains on Saturn’s largest moon, Titan, are named for mountains from Middle-earth, the fictional setting in fantasy novels by J.R.R. Tolkien. Unfortunately for “Lord of the Rings” fans, Titan’s highest peak is not Doom Mons, but a trio of ridges known as Mithrim Montes, where the tallest peak is 10,948 feet (3,337 metres) high.
Are you looking for something to bring the wow factor back to your public viewing sessions, or a means to observe in comfort out of the cold? The sub-£100 Astro-Video Systems DSO-1 camera promises near realtime colour imaging of deep-sky objects and high-resolution planetary imaging with modest telescopes. Does it deliver? Ade Ashford finds out.
Mercury is currently putting on a fine show in the east before dawn. Find a UK location with an unobstructed view due east an hour before sunrise to see the innermost planet some 6 degrees above the horizon from about 25 September—5 October. The very old crescent Moon lies just 2 degrees from Mercury at dawn on Thursday, 29 September.