Huygens Heads for Titan
At about 7:25 p.m. JPL time Christmas Eve, anxious scientists and engineers watching their monitors received bits from 800 million miles away, indicating that the Cassini spacecraft had successfully released the Huygens Probe over an hour earlier, with no faults or problems, right on schedule. In mission control, engineers with Santa hats could be seen cheering, clapping, shaking hands and congratulating one another. Some sample news reports: BBC News, MSNBC, Jet Propulsion Laboratory. Twelve hours after release, the Cassini orbiter snapped this photo of the distant probe flying away.
This begins the Probe’s 22-day solo flight to smog-shrouded Titan, where its three parachutes will deploy in sequence on January 14 to settle the 700-pound craft on the surface of the largest piece of unexplored real estate in the solar system. For some good accounts of the Huygens mission, see Space.com, BBC News, National Geographic News, and the official press releases at European Space Agency and Jet Propulsion Laboratory. Take a look also at Astronomy Picture of the Day artwork of Huygens Arrival and Probe Landing. (Unlike in the artwork, however, Saturn would not be visible, because it will be behind the moon from the landing spot, and the Cassini orbiter, of course, would be way too far away to see.) The Planetary Society has also been posting numerous articles about Titan. For the technically minded, there is a 68-page press kit, and for all ages, JPL has a photo essay. The ESA Site has some cool animations showing the orbital path of the probe.
Before signing off for Christmas, let’s review some of the other recent findings from Cassini. Some exciting news was announced at last week’s conference of the American Geophysical Union in San Francisco:
- Titan’s atmosphere was shown to be composed of multiple layers.
- Saturn’s atmosphere was shown to have multiple cyclonic storms similar to those on Jupiter, one resembling the Great Red Spot.
- Titan’s clouds have been observed to change, indicating there is active weather in the atmosphere. News@Nature also reported this item.
- The highest resolution pictures ever of icy moon Dione solved a 23-year old mystery. Voyager had photographed wispy streaks that were thought to be frost. It was just an optical illusion. The photographs show, instead, a series of grooves and trenches with steep, bright walls that reflect sunlight in a way that had produced the illusion of surface frost. Some of the surprise reaction can be found on The Planetary Society website and News@Nature, where the lead imaging scientist called it the “one of the most surprising results so far… It just wasn’t what we expected.” Dione’s black-and-white dullness stands out sharply against Saturn’s color in another Cassini image.
- More information was shared about erosion in Saturn’s E Ring (see 07/02/2004 headline), indicating the ring is being destroyed rapidly and cannot be as old as the solar system.
- Saturn has lightning a million times stronger than the bolts on earth; see story on Astrobiology.com; the principal investigator at U of Iowa said the find is “astonishing”.
- The varying rotation rate since Voyager is also difficult to explain, said the RPWS team from U of Iowa. It may mean that Saturn’s magnetic field does not rotate as a rigid body.
Watch for exciting news from Titan on January 14-15. There are not many “first time ever” adventures left in the solar system, and this should be one of the best in our lifetime. Congratulations to the many team members, some of whom have been working for 20 years for this moment. What will Huygens see as it samples, measures and photographs the atmosphere and surface of this bizarre, frozen world that is bigger than Mercury and Pluto? The world may soon know.