What’s Up for September: Jupiter

Hello and welcome. I’m Jane Houston Jones at NASA’s Jet Propulsion Laboratory in Pasadena, California.

2009 is International Year of Astronomy.

Each month this year we’ll be showcasing a great celestial object, and this month it’s the planet Jupiter.

We’ll also be telling you about Juno, a mission to that giant planet, which launches in 2011.

Jupiter is the brightest object in the evening sky this month. Through a telescope you can see cloud bands on Jupiter.

In July a small comet or icy body crashed into Jupiter’s southern polar area and left a black bruise.

This new, dark feature was discovered by Anthony Wesley, an amateur astronomer in Australia.

This spot captivated Jupiter observers for over a month while Jupiter’s atmosphere distorted its shape. And it finally dissipated.

This amazing feature has been imaged and studied by amateur and professional astronomers around the world.

Jupiter also has four large satellites, three of which are larger than our own moon.

These four moons were discovered by Galileo 400 years ago.

You can see them yourself with a small telescope or even binoculars,and watch them move around the planet just as Galileo did!

NASA’s spacecraft named for Galileo ended its exploration of Jupiter six years ago.

The next mission to Jupiter, called Juno, will launch in 2011. Juno will be the first solar-powered spacecraft to visit an outer planet and the first to have a polar orbit around an outer planet.

This gives Juno a unique view of the planet, including the polar auroras – the northern and southern lights.

It also lets the spacecraft get very close to Jupiter, while avoiding the planet’s dangerous radiation belts.

Juno will look for important clues about Jupiter's formation by measuring how much water is there.

It will also investigate the planet’s internal structure, searching for a central core, and will learn how and where inside the planet Jupiter’s powerful magnetic field is generated.

The mission will look deeper into Jupiter than we’ve ever been able to before to see how the planet’s visible atmosphere and features, like the famous Great Red Spot, are shaped by currents in Jupiter’s deep interior.

Jupiter rules the evening skies this month, so go out and take a look!

And Juno arrives at this king of the planets in 2016.

There’s one other object in the evening sky this month worth mentioning. The asteroid Juno,one of the first four asteroids ever discovered, is bright enough to see with a pair of binoculars this month.

All you have to know is where to look.

You can learn all about NASA’s missions at www.nasa.gov.

That’s all for this month. I’m Jane Houston Jones.