Skywatchers in the UK and Western Europe should look low in the southern sky at 12am local time on 17, 18 and 19 June to see the waxing gibbous Moon in the vicinity of planets Mars and Saturn, plus first-magnitude star Antares in the constellation of Scorpius. This looping animation shows the passage of the Moon through this region of sky at the stated times for an observer in the centre of the British Isles. For scale, the view is 40 degrees wide, or twice the span of an outstretched hand at arm’s length. Note that the Moon’s size has been slightly enlarged for clarity. Click the graphic for a full-size version. AN animation by Ade Ashford.In an earlier post, I drew your attention to the Moon‘s close approach to Jupiter at dusk on 11 June, essentially the planet’s swan song of this apparition. Six nights later, the Moon’s orbital motion brings it between two prime-time planets: Mars and Saturn.
The Red Planet was closest to Earth at the end of May (see this story for the details), so it is still at its best during 2016, despite the very low altitude as seen from the UK. Currently highest in the sky due south at dusk, ochre-colour Mars is shining at magnitude -1.8 — brighter than any star.
This labelled computer-generated map of the Red Planet obtained through our interactive Mars Mapper app shows the Martian hemisphere facing Earth mid-June at around 11:30pm BST. The map has south up and east to the right. Click the graphic to launch Mars Mapper in a new window. AN graphic by Ade Ashford.Late into the night of Friday, 17 June, when the gibbous lunar disc is close to Mars, the planet has an angular diameter slightly less than 18 arcseconds. This means that the Red Planet requires a telescope magnifying 100x to enlarge it to the same size as the Moon appears to the unaided eye. You can use our interactive Mars Mapper to help identify Martian surface features. Note that the planet’s prominent v-shaped Syrtis Major is well placed mid-month for observers in the British Isles.
Ringed planet Saturn was at opposition on 3 June, so it is still at its closest to Earth for the year. Like Mars, the planet’s low altitude as seen from the UK will mean that poor seeing will make observations challenging, but on slightly misty nights when a high pressure weather system sits overhead, the jewel of the planets is still an arresting sight. At 18 arcseconds in diameter, Saturn’s disc is currently fractionally larger than Mars, while the northern aspect of its 42-arcsecond-wide ring system is prominently displayed.
Inside the magazine
Find out all you need to know about what is currently happening in the night sky and how to observe it in the June 2016 edition of Astronomy Now.
NASA’s Curiosity rover on Mars is currently on the lower slopes of Mount Sharp in a region covered in sandstone where it has just drilled its fifth prospecting hole. Two weeks ago, still in the same general vicinity, Curiosity took a pair of long-range scenic images toward higher regions of the mountain — beautiful views worthy of a postcard home.
On the morning of Wednesday, 6 April experienced observers in the British Isles with a clear sky living south of a line drawn between Galway in Ireland, Dumfries in Scotland and Berwick-upon-Tweed in Northumberland can potentially observe planet Venus slip behind the northern polar regions of the 28-day-old waning crescent Moon. But beware: the Sun lies just 16 degrees away.
A rover NASA plans to launch to Mars in 2020 will likely explore one of three locations selected last week by a scientific advisory group, which picked candidate landing sites that were once homes to ancient lakes and hot springs.
