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.
Friday, 27 July sees the second total lunar eclipse of 2018, which also happens to be the longest of the 21st century. Observers in Antarctica, Australasia, Russia, Asia, Africa, Scandanavia, Europe, Central and Eastern South America will see the event. The Moon rises at mid-eclipse as seen from the British Isles, some 6 degrees north of Mars at opposition.
In the remaining days of October and early into November, a fascinating series of planetary peregrinations plays out low in the East before dawn twilight gets too bright. Venus, like a sprinter on the inside lane of a running track, overtakes both Jupiter in Mars in two readily observable conjunctions set against the stellar backdrop of constellations Leo and Virgo.
Observers in the British Isles with a clear sky one hour after sunset on 24 August should find a location that offers an unobstructed view of the south-southwest horizon. Here you will see first-magnitude star Antares in the constellation Scorpius, Mars and Saturn all in a line easily encompassed by low-power binoculars in the bright twilight.
