Look to the southern sky at dusk on 12 January to see the 6-day-old waxing crescent Moon just 6½ degrees below magnitude +0.6 Mars in the constellation of Pisces. If you own wide-angle 7× or 8× binoculars, you can see the pair in the same field of view. Note that the Moon’s apparent size has been enlarged for clarity in this illustration. AN graphic by Ade Ashford.Observers in the British Isles and Western Europe looking up at the waxing lunar crescent around nautical dusk (some 1½ hours after sunset in the UK) on Saturday, 12 January will notice that the Moon is not alone – an orange-coloured magnitude +0.6 ‘star’ lies less than a span of a fist at arm’s length above it. This bright interloper in the otherwise modest stars of the constellation of Pisces is none other than Mars.
Some 24 weeks after its close opposition of 2018, the Red Planet presently lies almost 204 million kilometres from Earth, hence its tiny gibbous disc spans just 6.9 arcseconds. Not surprisingly, little in the way of martian surface detail will be evident except in large backyard instruments.
Our Moon has half the physical diameter of Mars, but the Red Planet appears so much smaller since it lies more than 500 times farther away this night. In fact, you need a telescope magnifying in excess of 260× to enlarge Mars to the same apparent size as the adjacent Moon appears to the unaided eye on 12 January.
The Curiosity Mars rover used a camera on the end of its robot arm to take a selfie on the slopes of Mount Sharp before moving on to begin exploring nearby clay-rich soils. The rover is slowly working its way up the lower slopes of the mountain, looking for changes that might indicate the transition from warmer, wetter eras to the dry, frigid environment seen today.
Look to the north-west this evening (21 May), soon after sunset, to enjoy a spectacular coming together of brilliant Venus and shy and elusive Mercury.
NASA’s Cassini spacecraft captured this view of Saturn’s moon Enceladus that shows wrinkled plains that are remarkably youthful in appearance, being generally free of large impact craters.