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Huygens
The Solar System > This Monday marks the anniversary of an historic event in interplanetary space travel. It was a mere three years ago when the Huygens probe landed on Titan, the largest and arguably the most mysterious of Saturn's sixty moons.
The probe was named for Christian Huygens, a Dutchman of extraordinary talents. Neither he nor the namesake probe are well known by the general public, but both played an important role in moving us forward in this discipline of astronomy.
Huygens lived in the 17th century, the real kickstart century for the scientific revolution. He was well educated in... well, a lot of things. He studied law and mathematics at first but eventually wandered into physics and astronomy. He dabbled with and invented and engineered two types of instruments that play huge roles in astronomy: clocks and telescopes. He was a man of many hats. In the truest sense of the term, he was an educated person.
More specific to what we are talking about now, it was in the late 1650's that the overactive Huygens developed a better way to grind lenses and with these constructed some wonderful telescopes. He used his refined telescopes to confirm that Saturn's strange and unexplained rings were not appendages growing out the side of Saturn, nor were they one solid disk of material. They were collections of innumerable "rocks" orbiting about the planet.
Moreover, with his scopes he discovered a moon around Saturn, a behemothic moon later christened Titan.
As time went on and telescopes got better, it became clear that Titan was a special satellite. It was more than 1000 miles larger across than our own moon. It is even larger than Mercury. But what set it apart was not just its extra large girth - it was a moon with an atmosphere.
Before we sent the Cassini-Huygens spacecraft there, not much was known of Titan. Its hazy atmosphere prevented scientists from seeing the surface. What was below? Was there just a rocky surface? Were there lakes and oceans of methane as predicted by temperature and pressure data?
When NASA sent the Cassini spacecraft to Saturn in the 1990's they efficiently decided to kill two birds with one stone. On board the massive Cassini spacecraft they would piggyback a smaller bundle of instruments - a bundle with a parachute.
This probe, named Huygens, would be released from Cassini to fall onto Titan, recording the whole journey along the way.
Well, three years ago Huygens fell to its destination and landed on the mystery moon, dropping through the haze and landing successfully on its surface. What Huygens and the Cassini spacecraft flying above discovered was not exactly what planetary scientists were hoping for.
It had long been thought that Titan might be covered in shallow seas of methane and ethane, hydrocarbons which are gases on our planet, but which on bitter cold Titan would be liquid.
Although Huygens snapped some pictures of what seemed to be liquid-worn terrain, the oceans were not to be found. Such is science; sometimes revealing the truth about something can take some the fun out of it.
Huygens also sent back images from the frozen surface itself, and eerie place surrounded in a kind of "sand" made of water ice.
The little trooper of a spaceprobe breathed its last after just an hour and a half on the surface. But Cassini, the mothership that brought Huygens to Titan, is still making the papers, sending back those incredible images of Saturn and snapping pictures of Saturn's moons as it flies by them. Just last week Cassini flew by Titan again, revisiting Huygens' final resting place.
If you can, take a virtual trip to Titan and Saturn at saturn.jpl.nasa.gov, and see the images both spacecraft have sent back. And if you can, grab a telescope this season and discover for yourself both the ringed giant Saturn and tiny Titan next to it, just as a young Christian Huygens did over 350 years ago.
Posted by Mark Ritter at 2008.01.13 03:54 PM | Comments (0)
