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Sprawled beneath a pale orange sky, the foreign wind rustling its recently discharged parachute, a solitary probe sent its first signal to expectant earthlings nearly a billion miles away.

Last month, the Huygens probe landed with a “splat” on Saturn’s largest moon, Titan, sending back the first physical data from the only moon in the solar system known to have an atmosphere, said Linda Spilker, Cassini project deputy scientist and co-investigator for the infrared spectrometer on-board Cassini.

The probe was launched successfully last December from Cassini, a satellite that has been orbiting and investigating the planet since July of 2004.

Titan’s atmosphere is thought to resemble that of primitive Earth, giving some scientists the hope that the Huygens data will tell scientists more about how Earth’s atmosphere evolved.

“(We were) just ecstatic,” said Krishan Khurana, professor of space physics at UCLA and member of the team of UCLA scientists who worked on Cassini’s magnetic field detector. “The mission was a complete success in every way imaginable.”

Since Titan’s orange atmosphere is too thick to allow a passing satellite such as Cassini to see its surface, Spilker said, the 700-pound probe, nine feet in diameter, has given scientists their first close-up look at a moon larger than the planet Mercury.

“Titan is the biggest moon of Saturn and it has the densest atmosphere of any moon in the solar system,” said Christopher Russell, professor of earth and space science and co-investigator for the magnetometer on-board Cassini. “Both characteristics made Titan very interesting to scientists.”

With a covey of cameras, a microphone and instruments for measuring air composition, pressure, temperature and wind speed, the Huygens probe sent back nearly four hours of data, which included a two and a half hour parachute-assisted plummet to the ground, and more than an hour of ground-based measurements.

The data shows that Titan seems to be able to retain its atmosphere, Khurana said, further linking it to Earth, which was also able to maintain its atmosphere.

“We should be able to come up with a fairly good idea about the future of this atmosphere,” Khurana said. “Understanding Titan’s atmosphere would be equivalent to learning about the primitive Earth’s atmosphere.”

Spilker said she was amazed by how remarkably similar Titan’s weather system seems to be to Earth’s.

“But Titan does not have a water-based weather system and its surface does not contain silicate rock,” Russell said. “The moon (Titan) is very different than the Earth in its weather system, yet the resulting erosion on the surface – whatever it is made of – is much the same as we would find here on Earth.”

Spilker explains that scientists think methane may play the role that water fulfills on Earth, since Titan’s 290-degree Fahrenheit environment is too cold to support liquid water.

“Methane is working as rain would work (on Earth),” Spilker said.

The probe landed on what Spilker said might have been a dry lake bed, full of “icy pebbles” made of water.

Though all of the retrievable data has been collected from the Huygens probe, Spilker says it will take several months to process it. Meanwhile, she says she hopes scientists will be able to use the available data to answer questions about Titan’s atmosphere.

“It’s interesting to understand exactly how weather works on Titan, to put together a complete model for Titan’s atmosphere,” Spilker said.