Viewing Jupiter - especially this 20th September 2010!


On September 20th 2010, Jupiter will be making its closest pass by Earth for the year – so what better reason to whip out your telescopes? As the 4th brightest object in the sky (after the sun, moon and the planet Venus), you shouldn't have to much trouble finding it!

This year's pass is closer than any other pass that has and will take place between 1963 and 2022, so be sure not to miss it!

Relative location of Jupiter to the moon
Image courtesy of Sky and Telescope

Far brighter than any true star in the night sky, it appear low in the east after twilight, and higher in the southeast as the evening grows late. Made of 90% hydrogen and 10% helium, you will also find traces of methane, water, ammonia and rock in Jupiter's composition.

Legendary planetary observer Richard Schmude, Jupiter will appear brighter - by about 4% - on the 20th of September as the brown cloud belts have gone missing.

As an “oblate spheroid”, it is slightly flattened on the top and bottom, and bulges around the equator. With a pair of astronomy binoculars, you'll be able to see all of Jupiter's 4 moons, but you will get far more detail with a telescope.

Jupiter is the largest planet in the solar system, and is the fifth planet from the sun. Roughly 2 ½ times the size of all the other planets combined, it can sometimes be seen with the naked eye.

Jupiter is but one of four Jovian (the adjectival name for Jupiter) giant gas planets, Jupiter is similar in composition to Saturn, Uranus and Neptune. Jupiter's surface isn't solid - it's really merely a giant ball of gas. The gases on the planet get denser with depth, but never dense enought to form a sold state.

There is a thick cloud layer over the surface over Jupiter's surface, with three distinct layers of ammonia, ice and ammonia hydro sulfide and a mixture of ice and water. Forming three distinct banks that move around the planet in different directions - each band has different temperatires and chemical compositions. The darker bands are called belts, and the lighter bands are called zones.

Visible even to most novice stargazers, Jupiter's a great beginner's planet to set your sights on.