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.
Researchers using NASA’s Mars Reconnaissance Orbiter have determined that frozen beneath a region of cracked and pitted plains on the Red Planet there lies about as much water as fills Lake Superior, largest of the Great Lakes. Scientists examined part of Mars’ Utopia Planitia region with the orbiter’s ground-penetrating instrument, revealing a deposit more extensive in area than the state of New Mexico.
NASA’s Curiosity Mars rover has used its drill to collect sample powder from inside a rock target called “Telegraph Peak.” Examining rock samples like these will help scientists understand how the ancient wet environment of Mars dried up.
Saturn’s moon Dione received a fleeting visitor on 16 June, when NASA’s Cassini spacecraft whizzed by to image bizarre streaks thought to be canyons with ice walls up to 100 stories tall.