Space Probe Headed for a Record Landing
The probe is set to land on Saturn’s moon Titan on Jan. 14.
On target for Titan, Saturn’s haze-shrouded moon, the Huygens space probe is headed for a mystery-packed landing.
The European Space Agency’s Huygens lander successfully detached from the international Cassini spacecraft on Christmas Eve and now speeds toward Titan on a precise trajectory to enter the moon’s orange-tinged atmosphere. Whether the 705-pound probe will land on frozen ice, a methane lake or a muddy combination of both remains uncertain.
On Jan. 14, Huygens’ landing — the farthest one from Earth ever attempted by any space probe — is expected to be a scientific highlight of 2005. The second-largest moon in the solar system and the only one with a dense atmosphere, Titan fascinates planetary scientists. Under its dense clouds, a complex interplay of carbon chemistry is thought to take place, mirroring conditions on Earth at the birth of the solar system.
So far, NASA scientists have pronounced themselves boggled by the cloudy glimpses seen on recent fly-bys, a vista of light and dark plateaus that mesh jaggedly, marked by windswept features with hints of frozen lakes seen in radar images.
“Despite everything we’ve seen, Titan is almost as mysterious now as it was 15 years ago,” says Huygens chief scientist John Zarnecki of the United Kingdom’s Open University.
On entry, Huygens will plunge into Titan’s clouds at a 65-degree angle, hitting speeds near 13,000 mph and raising temperatures on its heat shield to more than 2,700 degrees Fahrenheit.
“That’s damn fast, a fireball entry,” says Zarnecki, who calls those moments the “most terrifying” of the probe’s voyage from Earth to Titan. After its speed drops, the probe will deploy three parachutes and measure the density of Titan’s atmosphere as it drifts down, with luck returning at least two hours of photos and data to Cassini.
Cassini-Huygens is a $3.27 billion collaboration between NASA, the European Space Agency and the Italian Space Agency, on a four- year mission to explore Saturn and its 31 known moons.