The serene beauty of the International Space Station gliding silently across the sky needs nothing more than the naked eye to appreciate. But when the dazzling ISS is also in conjunction with a partially eclipsed Moon, Saturn and Jupiter on the 50th anniversary of Apollo 11’s launch, be sure to look low in the southeast through south around 10:06pm BST on 16 July 2019!
Observers in Western Europe with a clear sky around local midnight cannot fail to notice the conspicuous ‘star’ that is Jupiter low in the south. But look a span-and-a-half of an outstretched hand at arm’s length to Jupiter’s left and you’ll find another giant of the solar system – Saturn. The ringed planet is closest to Earth for 2019 on 9 July, so here is our quick observing guide.
July opens with Jupiter three weeks after opposition, but the largest planet is still putting on a fine show as an unmistakable magnitude -2.6 object low in the south before midnight in the constellation of Ophiuchus (the Serpent Bearer). With ongoing developments in the Jupiter’s Great Red Spot and plenty of phenomena occurring with the planet’s large Galilean moons, here’s our Jovian observing guide for July 2019.
The Great Red Spot (GRS) is the solar system’s largest known storm, an Earth-sized anticyclone that has raged in the atmosphere of Jupiter for at least two centuries. But recent observations from Earth and space suggest that this iconic Jovian feature is undergoing huge changes that could herald its demise.
On 18 June at the end of civil twilight in the UK, planets Mars and Mercury lie slightly less than one-quarter of a degree apart in the constellation of Gemini. Observing this conjunction will be a challenge from the UK as the pair will be just 5 degrees high in the west-northwest at civil dusk in bright twilight, which is about 50 minutes after sunset for London.
Jupiter, the solar system’s largest planet, reaches opposition on 10 June in the constellation of Ophiuchus (the Serpent Bearer) and is visible low in the southern sky of the UK through the night. Observers with small to medium aperture telescopes can see a number of shadow transits of Jupiter’s Galilean moons and view the planet’s Great Red Spot throughout June.
Have you ever seen a dwarf planet? Of the five within our solar system recognised by the International Astronomical Union – Ceres, Pluto, Haumea, Makemake and Eris – only Ceres can be considered bright and easy to locate. It reaches opposition in the constellation of Scorpius on 29 May at magnitude +7, an easy binocular object if you follow our guide.
Observers in the UK with clear skies around 1am BST on Tuesday, 21 May can see Jupiter, the solar system’s largest planet, just 4 degrees from the waning gibbous Moon low in the south-southeast. At this time both the Moon and Jupiter fit within the same field of view of binoculars magnifying less than 10×, while telescope users can also view Jupiter’s Great Red Spot.
UK skywatchers with a view low to the west between midnight and moonset on Saturday, 11 May 2019 can see the 6-day-old waxing crescent Moon close to Messier 44, otherwise known as Praesepe, or the Beehive Cluster. Later, observers on North America’s Eastern Seaboard can see the Moon pass in front of this glorious open cluster just before local midnight on 10 May.
If you’re bemoaning the current dearth of bright planets in the evening sky, or light pollution prevents you from viewing a multitude of spring galaxies, don’t give up – there are always attractively coloured double and multiple stars to view. Join us on a tour of the Northern Hemisphere constellation of Boötes (pronounced Bo-oh-tees), the Herdsman, easily located due to its brightest star, Arcturus.