http://sg.news.yahoo.com/afp/20080527/tts-us-space-astronomy-mars-972e412.html
NASA probe sends first pictures from Martian arctic
AFP - Wednesday, May 28
WASHINGTON, (AFP) - - A NASA probe sent back never-before-seen
pictures of Mars' north pole Monday, in the most ambitious mission
to date to find if the Red Planet could support
life.ADVERTISEMENT
After NASA's Phoenix Mars probe made a near perfect landing at the
Martian polar region late Sunday, scientists pored over images
revealing a desolate frozen tundra.
Given that Mars ' polar region is subject to Earth-like seasonal
changes, the scientists think that, like on Earth, the Martian
arctic might have a geological record of a warmer, habitable
climate.
"We can see cracks in the troughs that make us think the ice is
still modifying the surface," said Peter Smith, a lead scientist on
the project. "We see fresh cracks. Cracks can't be old. They would
fill in," he said.
Scientists said they were also excited about the images taken by
the probe during its descent late Sunday into the atmosphere of the
Red Planet.
"I'm floored. I'm absolutely floored," said Phoenix Project manager
Barry Goldstein of NASA's Jet Propulsion Laboratory in Pasadena,
California, as he reviewed the dramatic images.
Phoenix on Monday was to test several of its instruments and
systems, while continuing to transmit back to Earth images of its
surroundings.
The pictures from the probe confirmed that the solar arrays needed
for the mission's energy supply had unfolded properly, as the
craft's batteries would have run out in about 30 hours.
The photos also showed masts for the stereo camera and weather
station had swung into vertical position as planned, and showed the
spacecraft's footpad planted on the dusty surface as well polygonal
patterns on the ground that looked similar to icy arctic regions on
Earth.
The flat Martian valley floor is expected to have water-rich
permafrost within reach of the lander's robotic arm.
"Seeing these images after a successful landing reaffirmed the
thorough work over the past five years by a great team," Goldstein
told reporters.
After a nine-month journey from Earth, the Phoenix probe touched
down in a relatively flat target area.
As planned, Phoenix stopped transmitting signals one minute after
landing and focused its limited battery power on opening its solar
arrays, and other critical activities.
But a key task still ahead was the first use of the lander's
robotic arm, which was planned for Tuesday.
The backhoe-like arm, 2.35 meters (7.7 feet) long, is designed to
dig trenches up to one meter (3.3 feet) deep for samples of soil
and water ice.
The arm will deliver the samples to instruments aboard the lander
for detailed chemical and geological analysis.
The robotic arm also carries a box-shaped camera with a double
Gauss lens system like that in 35mm cameras, and two lighting
assemblies.
This will take images of the surrounding area and of samples the
arm picks up.
Another camera device is the surface stereo imager, what NASA calls
Phoenix's "eyes." Sitting two meters (6.6 feet) above the ground,
the SSI will produce high-definition and panoramic images of the
surrounding landscape.
Its stereo capability will help give scientists on Earth
three-dimensional views of the work the robotic arm does. It can
also be turned vertically to take images that will provide
information on atmospheric particles.
"Only five of our planet's 11 previous attempts to land on the Red
Planet have succeeded," said Ed Weiler, NASA associate
administrator. "In exploring the universe, we accept some risk in
exchange for the potential of great scientific rewards."
Working in the flat circumpolar region known as Vastitas Borealis
-- akin to northern Canada in Earth's latitude -- Phoenix, with a
panoply of high-tech equipment, will over three months dig below
the surface to probe the icy ground for signs of liquid water and
organic, life-supporting minerals.
The team had been worried about the high risk of the project, with
a roughly 50 percent failure rate on all Mars missions since the
Soviet Union launched the first one in 1960.