Magnitude +2.9 star Mu (μ) Geminorum, better nown as Tejat in the constellation of Gemini, is occulted (hidden) by the rising 13-day-old waxing gibbous Moon early on the evening of Thursday, 9 January 2020 as seen from the British Isles. This graphic shows the event’s progress as seen from London and Edinburgh, clearly demonstrating the effect of geographical latitude. AN graphic by Ade Ashford.If the early evening sky of Thursday, 9 January is clear, observers in the British Isles get the opportunity to witness a conspicuous naked-eye star slip behind the rising waxing gibbous Moon. Magnitude +2.9 Mu (μ) Geminorum, with the proper name Tejat, lies near the western edge of the constellation Gemini. The precise time and duration of the star’s disappearance behind the Moon – an event known as a lunar occultation, from the Latin occulo, ‘to hide’ – depends on where you live in the UK.
Observers in London will see, weather permitting, Tejat disappear at the darkened limb (edge) of the 13-day-old Moon shortly after 5:05pm GMT (17:05 UT) and reappear at the bright lunar limb 45 minutes later. For a skywatcher in Edinburgh, the star’s corresponding disappearance and reappearance times are a few seconds before 5:17pm GMT (17:17 UT) and 5:52pm GMT, respectively.
Mid-occultation of Tejat takes place with the Moon some 15 degrees (about a span-and-a-half of a fist held at arm’s length) above the UK’s east-northeast horizon. While it is an easy spectacle to follow in a small telescope, the star’s reappearance at the bright lunar limb might be a challenge for binocular users. As with all occultation observations, it pays to be setup and scrutinising the Moon 10 minutes before the predicted times, particularly if you live some distance from either London or Edinburgh.
As dusk fades to dark on Saturday, 11 June, observers in the British Isles should look low in the western sky to see the 7-day-old waxing crescent Moon and Jupiter less than 3 degrees apart, within the same binocular field of view. Get your observations in now as the solar system’s largest planet is poised to leave the celestial stage during the summer.
A camera developed by scientists at Arizona State University will join four foreign-built instruments on South Korea’s first lunar orbiter set for launch at the end of 2018, NASA announced Friday.
Now two months past opposition, the solar system’s largest planet, Jupiter, is highest in the UK sky before sunset and is already descending in the southwest by the time the sky is dark enough to observe it. However, there is still phenomena of the Galilean moons to see and the planet’s Great Red Spot, so make the most of your Jovian observations while you can during May.
