[meteorite-list] Russia Planning Double Assault on Mars
Ron Baalke
baalke at zagami.jpl.nasa.gov
Fri Jun 24 15:43:40 EDT 2005
http://www.newscientistspace.com/channel/solar-system/dn7576
Russia planning double assault on Mars
Kelly Young
New Scientist
June 24, 2005
Russia is planning two uncrewed Mars missions, according to press reports.
The first, in 2009, is a mission to orbit Mars and land on the tiny moon
Phobos, where a rover would roam for three years. There, it would
collect samples of soil to bring back to Earth - the first ever if
successful. The second mission, scheduled for 2015, is to place a lander
on the surface of the Red Planet.
But Russia has had little success in its Martian missions. Since 1960,
Russia, and the Soviet Union before it, has tried to send 17 probes to
Mars - only three of those were unqualified successes.
The Phobos 1 and 2 missions were dispatched to the Martian moon in 1988,
but one failed on the way because of a software error. The other made it
into orbit around Mars but a computer glitch prevented it from deploying
a lander to Phobos' surface. Russia's most recent attempt to conquer the
Red Planet was in 1996, when its Mars-96 orbiter did not even get out of
Earth orbit.
Russia has been working on a Phobos mission for several years, says a
report by the UPI press agency. In theory, it should be easier to land
on the Martian moons because a probe would only have to move alongside
another orbiting object, rather than decelerate rapidly through the
planet's atmosphere. A sample return mission would also use less fuel
escaping the tiny gravity of a moon compared to leaving the much larger
planet.
Kicking up dust
A further advantage of landing on Phobos is that it is very close to
Mars - just 9000 kilometres above the surface. From that vantage point,
a spacecraft could also make detailed measurements of Mars.
The proximity of Mars means Phobos is likely to have pieces of the
planet on it. When large meteorites crash into Mars, they kick up rocks
and soil. The finest particles are launched into orbit around Mars,
where Phobos sweeps some of them up.
But collecting grains of Martian dust from Phobos would not tell
scientists a lot about where the particles originated or how old they
are. "You learn a lot more about Mars if you know where the rock came
from," says Phil Christensen, a geologist at Arizona State University in
Tempe, US, who has worked on several of NASA's Mars missions.
Meteorites found on Earth that originated on Mars suffer the same
drawback. "But the bottom line is we don't know a lot about Phobos
either," he adds.
Martian moon base
The US has never devoted a mission to Phobos or its sister moon Deimos
although other Martian orbiters have snapped pictures of the pair. The
moons do not have the obvious allure of Mars: interesting climate, a
history of water and the prospect of life.
"Phobos and Deimos don't have those attractions, but they're attractive
in their own right," says Fred Singer, president of the Science and
Environmental Policy Project in Virginia, US. "Once you decide to do a
proper manned missions, you should think about Phobos and Deimos."
Singer says setting up a crewed base on Deimos would be cheaper and
easier than sending humans to the Martian surface.
A mission devoted to the moons could explain how the satellites are held
together - whether they are piles of rubble loosely held together by
gravity or solid chunks.
Most scientists assume the heavily cratered moons are captured
asteroids, Christensen told New Scientist. But it is actually quite hard
for a planet to capture an object into its orbit - most things just skim
by. "So how it got there is a bit of an enigma," Christensen says.
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