Starwatch: an exercise in opposites – the Moon and Jupiter

Starwatch Monday 21 May, 2018

The Moon joins Jupiter in the constellation of Libra for a close approach on 27 May. The Moon will be in its waxing gibbous phase, heading towards full on 29 May. Jupiter is now a few weeks past its closest approach to Earth and will remain a fabulously bright evening object visible for most of the night. The chart shows the location for 23:00 BST on 27 May. The Moon and Jupiter are exercises in opposites. Whereas the Moon’s entire surface is comparable in area to the continent of Africa, Jupiter’s surface area is more than 120 times larger that the whole Earth. Jupiter’s “surface” however is nothing but clouds. The gas giant has no solid surface, the atmosphere just gets denser with depth until it turns into a highly compressed metallic liquid. The NASA Juno mission is currently in orbit around the planet trying to determine whether there is a solid rocky/metallic core buried at the centre of the planet.