Probe Set to Explore Saturn's Moon Titan

NASA/ESA

The Huygens probe approaching Saturn's moon Titan.

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Touchdown on Titan

Watch a NASA Animation of Huygens' Landing on Titan*

See an Animated Timeline of Huygen's Descent **

* Link goes directly to NASA's site. Quicktime required.

** Link goes directly to ESA's site. Click the "Ready" button to activate the timeline.

On Friday, the European space probe Huygens is set to parachute onto the surface of Saturn's moon Titan. If all goes well, Huygens will gather pictures, sounds and air samples as it falls through the moon's cloudy atmosphere -- helping flesh out the story of our solar system.

Named after Dutch astronomer Christiaan Huygens, who discovered Titan 350 years ago, the probe was released from its larger companion craft, Cassini, in late December.

As it parachutes onto Titan, Huygens will use the moon's atmosphere as a natural braking system. During its descent, expected to last just over two hours, the probe will take pictures, analyze the air and even record the sounds of Titan.

Scientists hope the data will help them better understand the layout of our solar system: how it came to have rocky planets near the sun, gas giants farther out and icy moons, like Titan, swirling around those giant balls of gas.

Observing the chemical reactions within Titan's atmosphere -- which contains nitrogen, methane and traces of ammonia, argon and ethane -- may also shed light on how life evolved here on Earth. NPR's Richard Harris reports.