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(CNN) -- Information from the first contact with the surface of an alien moon is arriving at radio telescopes around the world.
The Huygens probe sent a signal to scientists at NASA and the European Space Agency racing to decipher the long-distance message from Saturn's moon Titan. Radio telescopes confirmed the probe survived reentry, successfully deployed its three parachutes and landed on the moon's icy surface this morning.
The probe -- although designed to last only minutes on the moon's surface -- beamed data for nearly two hours to Cassini, in its orbit around Saturn.
Cassini received information until it passed beyond the moon's horizon and out of contact. Now Cassini has turned toward Earth and is passing on the data to scientists.
They are hoping the data have survived transmission uncorrupted, said Bob Mitchell, program manager for the Cassini-Huygens mission at NASA.
"What we know is the probe survived reentry.... descended the atmosphere, contacted the surface and transmitted for at least an hour and half," he said. "What we don't know is how did the instruments work, how did Cassini work and do we have the data intact."
Huygens reached the surface of Saturn's moon Titan on Friday around 7:45 ET, reported elated scientists from the European Space Agency, standing ready to analyze long-awaited data from the cloud-shrouded moon.
"We have a signal. We know that Huygens is alive meaning the dream is alive," said Jean-Jacques Dordain director general for ESA which designed Huygens. "This is already an engineering success and we will see, later this afternoon, if this is a scientific success."
Grinning scientists watching from the ESA operations center in Germany said the first obstacle -- a tricky atmospheric entry -- had been a great engineering feat. Time will tell if all of Huygens' precious data will reach their destination.
"So far so good," said David Southwood, director of science for ESA. "The signal has been solid for a long time."
The saucer-shaped probe has completed the final hours of its 2.2 billion-mile mission. Jean-Pierre Lebreton, Huygens project scientist, said the first data from a Doppler wind experiment has reached Earth and more data would arrive throughout the morning.
"It's going to be the most exotic place we've ever seen," said Candice Hansen, a scientist for the Cassini-Huygens mission. "We've never landed on the surface of an icy satellite. We know from our pictures that there are very different kinds of geological processes."
The Cassini-Huygens mission is an unprecedented $3.3-billion effort between NASA, the European Space Agency and Italy's space program to study Saturn and its 33 known moons. The two vehicles were launched together from Florida in 1997.
"The mission is to explore the entire Saturnian system in considerably greater detail than we have ever been able to do before: the atmosphere, the internal structure, the satellites, the rings, the magnetosphere," said Cassini program manager Bob Mitchell at NASA.
The Huygens probe, about the size of a Volkswagen Beetle, spun silently toward Titan after it detached from the Cassini spacecraft on December 24. Cassini will remain in orbit around Saturn until at least July 2008.
The mission "will probably help answer some of the big questions that NASA has in general about origins and where we came from and where life came from," Mitchell said.
Titan's atmosphere, a murky mix of nitrogen, methane and argon, resembles Earth's more than 3.8 billion years ago. Scientists think the moon may shed light on how life began.
Finding living organisms, however, is a remote possibility. "It is not out of the question, but it is certainly not the first place I would look," Hansen said. "It's really very cold." A lack of sunlight has put Titan into a deep-freeze. Temperatures hover around -292 F (-180 C) making liquid water scarce and hindering chemical reactions needed for organic life.
New discoveries
The mysteries of Saturn, the sixth planet from the sun, have always enticed researchers. Scientists are perplexed why Saturn, a gas-giant composed primarily of hydrogen and helium, releases more energy than it absorbs from faint sunlight. Titan is also the only moon in the solar system to retain a substantial atmosphere, one even thicker than Earth's.
The 703-pound, battery-powered Huygens probe parachuted through Titan's clouds of methane and nitrogen for two-and-a-half hours, sampling gases and capturing panoramic pictures along the way.
Huygens hit the upper atmosphere 789 miles (1,270 km) above the moon at a speed of about 13,700 mph (22,000 km/h). A series of three parachutes slowed the craft to just 15 mph (24 km/h). Chutes and special insulation protect Huygens from temperature swings and violent air currents. Strong winds -- in excess of 311 mph (500 km/h) -- buffeted the craft.
Its sensors deduced wind speed, atmospheric pressure and the conductivity of Titan's air. Methane clouds and possibly hydrocarbon rain was analyzed by an onboard gas chromatograph. A microphone listened for thunder.
Three rotating cameras took panoramic views of the moon and a radar altimeter mapped Titan's topography. A special lamp illuminated the probe's landing spot to help determine the surface composition.
Engineers had been confident that Huygens and its suite of six sensitive instruments would survive the descent.
"From an engineering standpoint, I'm very confident in a positive outcome," said Shaun Standley, an ESA systems engineer for Huygens at the Jet Propulsion Laboratory in California. "We've been over this again and again for the last three years fine-tuning this."
Cassini crossed Saturn's rings without mishap in June 2004 and produced the most revealing photos yet of the rings and massive gas-giant. A problem with the design of an antennae on Cassini almost scrapped Huygens' mission, but engineers altered the spacecrafts' flight plans to resolve the transmission problem.
