What’s Up for August 2011?

What's Up for August? The solar system's windy worlds.

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

Many of our planetary neighbors have significant atmospheres.

On Venus the atmosphere's much thicker than our own and blankets the planet with dense clouds, which can reach tornado-like speeds. On Mars it's much thinner, though there are periodic global dust storms and even dust devils.

The outer planets' atmospheres are worse than that.

Jupiter and Saturn's atmospheres are swirling with toxic gases like ammonia, and the temperatures and wind speeds are extreme. The Cassini spacecraft recently studied a huge storm on Saturn, which has been raging since last December. While it started as an isolated storm, the winds in Saturn's atmosphere have affected the tops of Saturn's clouds. The storm now completely encircles the planet, and can even be spotted in amateur telescopes.

In this false-color image the blue clouds are the highest and are thin. Yellow and white clouds are thick, high-altitude clouds. Green are intermediate. Red and brown are lower-altitude clouds but are not obscured by the other clouds.

The deepest blue shows a thin haze with no clouds below. The storm clouds are most likely made of water ice covered by crystallized ammonia, carbon and other contaminants.

But which planet is the windiest? Neptune.

The winds on Neptune blow at more than 1200 miles per hour. That's 2000 kilometers per hour.

Mission Control voice: Ignition. Lift off.

Jones: With the launch of the Juno spacecraft this month, we celebrate our return to Jupiter.

Juno will improve our understanding of our solar system's beginnings by revealing the origin and evolution of Jupiter.

The spinning spacecraft will use microwave antennas to observe how this windy world is moving far below its visible cloud tops. It will also probe Jupiter's interior to determine how deep, wind-driven cloud features, like the colorful bands and the Great Red Spot, reach into the planet.

Throughout August, Saturn is visible at sunset, and you can see Jupiter after midnight.

Both Neptune and asteroid Vesta are at opposition this month, but you'll need a telescope to see them.

You can read all about asteroids at solarsystem.nasa.gov/yss, for Year of the Solar System.

You can learn all about the Juno mission at http://www.nasa.gov/juno.

And you can learn all about NASA's missions at www.nasa.gov.

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