Observers in the UK with a clear sky high to the south-southeast shortly after midnight on Sunday, 12 January 2020 can see the 16-day-old waning gibbous Moon just three-quarters of a degree north of the beautiful open star cluster Messier 44, otherwise known as Praesepe, or the Beehive Cluster. AN graphic by Ade Ashford.If you own a pair of binoculars or a small telescope, you may wish to take a look at the Moon on the night of 11–12 January 2020 since it lies in the constellation of Cancer, the Crab. If you look a little more closely, you’ll see that the Moon lies in the same field of view as the glorious open star cluster known as Praesepe, the Beehive Cluster, or more prosaically as Messier 44.
For observers in the British Isles, the Moon’s orbital motion doesn’t bring it closest to the Beehive Cluster until the calendar clicks onto 12 January, by which time the pair are high in the south-southeast. At their closest – 12:30am GMT (00:30 UT) – the 16-day-old waning gibbous Moon lies just three-quarters of a degree north of the heart of Praesepe. In a telescope, use your lowest magnification eyepiece and watch as the Moon glides over the northern edge of M44, occulting (passing in front of) a number of its fainter stars.
For three evenings from 26–28 February 2020, observers in Western Europe including the British Isles can watch the waxing crescent Moon’s changing configuration with brightest planet Venus in the west-southwest at dusk. The pair are closest for UK-based observers on the evening of Thursday, 27 February, simultaneously visible in low-power binoculars.
Observers in Western Europe should look to the east an hour before sunrise on Monday, 18 September to see not only dazzling Venus and the old crescent Moon in the same binocular field of view, but planets Mars and Mercury against the stars of Leo too.
Astronomers believe that the Earth-Moon system was created in a giant impact 4.5 billion years ago. Southwest Research Institute scientists combined dynamical, thermal, and chemical models of the Moon’s formation to explain the relative lack of volatile elements like potassium, sodium, and zinc in lunar rocks, when compared to those of Earth.
