The Moons of Jupiter

Have you noticed a very bright object in the sky this month? Jupiter has been showing spectacularly well this autumn and can easily be found as it moves through the southern sky during the evening. Technically not seen in Bicknor Wood, but obvious in the night sky from the clearing with the burnt tree. If you watch for a while, it appears to move from left to right passing through direct south at around 8pm (through November). The second half of the month should give good views as the moon will be rising later and not dazzling your night vision.

Even when the moon was passing Jupiter earlier in the month, it was still easy to see our Solar System's largest planet and 4 of its moons.

11pm 04/11/2022

From closest proximity to the planet they are; Io (orbits every 1.8 Earth days), Europa (orbits in 3.6 Earth days), Ganymede (orbits in 7.2 Earth Days) and Callisto (orbits in 16.7 days). These are the four large Jovian moons known collectively as the Galilean Satellites. They can easily be seen with a pair of binoculars and even through a misty atmosphere.

7pm 11/11/2022

Their positions change rapidly and one or more can frequently be lost from view as they pass across the face or behind Jupiter, but as a general rule of thumb, they all orbit in the same plane and appear in a straight (-ish) line either side of their host. On 11th November. Io and Europa were eclipsed by Jupiter at 7pm, but were visible, having appeared from behind it by 11pm

11pm 11/11/2022

The Galilean Satellites were first observed by Galileo who instantly fell foul of the Church in Rome by reporting that they orbited around Jupiter. Up 'til then everything was supposed to orbit around the Earth and all was perfect in the heavens. Finding an anomaly in God's creation was considered heresy.