Huygens landed!

Congrats to the Cassini-Huygens team - perfect landing so far.......
Now for the science to come back!


http://edition.cnn.com/2005/TECH/spa...tan/index.html



The probe landed on the surface of Saturn's moon Titan this morning
around 7:45 ET, reported elated
scientists from the European Space Agency, who are eagerly awaiting
data about 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 Earth. The probe will continue sending data
until its batteries run out or
Cassini, the satellite orbiting Saturn relaying Huygens' signal,
passes over the moon's horizon in about
two hours' time.

"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 is completing the final hours of its 2.2
billion-mile mission to study the icy
world. It plunged through the orange clouds of Saturn's moon Titan
early Friday morning deploying three
parachutes to slow down from a blistering reentry speed.

Jean-Pierre Lebreton, Huygens project scientist, said the first data
from a Doppler wind experiment were
reaching Earth and more data would arrive throughout the morning.
Radio telescopes around the world are
tracking Huygens' signal.

When the first images arrive this afternoon, scientists will have
their long-anticipated glimpse at an
alien world.

"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 befo 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, has been
spinning silently toward Titan since 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, capable of
dragging Huygens sideways after its
parachute was deployed.

Its sensors can deduce wind speed, atmospheric pressure and the
conductivity of Titan's air. Methane
clouds and possibly hydrocarbon rain will be analyzed by an onboard
gas chromatograph. A microphone will
listen for thunder.

Three rotating cameras are snapping panoramic views of the moon,
capturing up to 1,100 images. A radar
altimeter is mapping Titan's topography and a special lamp illuminated
the probe's landing spot to help
determine the surface composition.

Engineers were 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.