What's Up August 2008: Jupiter reigns the night sky

It's Jupiter-viewing season.

I'm Jane Houston-Jones at NASA's Jet Propulsion Laboratory in Pasadena, California.

Jupiter is the largest of the planets in our solar system.

If you step outside and look in the southeast after it gets good and dark, you'll be able to see Jupiter. It'll be the brightest object in the sky.

Through a telescope, you'll see not only the planet but the four Galilean moons. Those are the four moons of Jupiter that Galileo discovered almost 400 years ago.

When you look through a telescope, you'll see some of the cloud bands. It'll look like there's colorful reddish-brown stripes on the planet's surface. But Jupiter doesn't actually have a surface. It's a big ball of gas, similar to Saturn.

And so what we're seeing are clouds as opposed to surface features.

Jupiter has one really amazing feature on it. And it's a large cyclone called the Great Red Spot. You can see this through amateur telescopes, but you do need to know when to look for it.

There've been many spacecraft that have studied Jupiter. Galileo is the only one that has orbited the planet. The Galileo spacecraft even dropped a probe into the atmosphere of Jupiter.

We have another mission to look forward to in a few years when Juno launches. It'll also be an orbiter and will study the polar areas of Jupiter.

That's all for this month.

I'm Jane Houston-Jones.