Jupiter

[Speke-EZY]

It's a beautiful clear (if chilly) evening offering a superb view of the giant planet Jupiter...roughly east of the moon.

A small telescope reveals three of the four Galilean moons (Io,Europa,Ganymede and Callisto) all to the left of Jupiter itself.

These objects can be seen to shift position in their orbits over the course of a couple of weeks so the fourth satellite should appear before long.

Well worth a few minutes if you like this sort of thing!

[ian531]

Hi

I have just noticed your thread, sorry I have duplicated this info.

Yours has much more information

Do you know the name of the fourth moon?

Ian

[Speke-EZY]

Hi Ian,

I was amused when I spotted your Jupiter report. No offence taken!

The four large satellites of Jupiter - known as the "Galilean moons" - because the early astronomer Galileo was able to see them through his very basic telescope - are called Io,Europa,Ganymede and Callisto. Recent space probes have sent back detailed images of these objects. Io (nearest orbit to Jupiter) is covered with many active volcanoes thought to be generated by the heat of tectonic tidal activity caused by the planet's massive gravitational forces. Europa is covered by frozen water ice several kilometres thick. There may be vast liquid oceans below this surface and Europa is said to be one of the most promising places in the Solar System in the search for extra-terrestrial life. Ganymede and Callisto in their remote orbits are by comparison quiet places,desolate rocky bodies much like our own Moon. Jupiter is now known to have many smaller satellites (more than twenty I think) but these are unlikely to be visible with the average spotting scope.

Hope this helps,Keith

[Speke-EZY]

For anyone who might be interested,all four of Jupiter's large moons are clearly visible this evening (one above the planet and to the left,the other three roughly in a line below and right). Venus is also very bright further to the west so it will set earlier, Venus has no satellites.