Nasa looks deep into Mars
2008-08-15 11:03
Los Angeles - Nasa's Mars Phoenix
Lander has sent back the first-ever image of a speck of red
Martian dust taken through an atomic force microscope, shown at
a higher magnification than anything ever seen from another
planet.
The dust particle is about one micrometre - or one
millionth of a metre - across and is representative of the
dust that cloaks Mars, producing the planet's distinctive red
soil and colouring its sky pink, Nasa said.
"This is the first picture of a clay-sized particle on
Mars, and the size agrees with predictions from the colours seen
in sunsets on the Red Planet," said Phoenix co-investigator Urs
Staufer of the University of Neuchatel, Switzerland, who leads
a Swiss consortium that made the lander's microscope.
Phoenix has been exploring the Martian arctic circle since
May 25 and has already provided definitive proof that ice and
water exist on Earth's planetary neighbour.
It is the latest Nasa spacecraft sent to Mars as the space
agency tries to determine if life, even in microbial form,
exists or ever existed there.
The new pictures were taken using Phoenix's on-board atomic
force microscope, which maps the particles in three dimensions
and can detail shapes as small as 1/1000th the width of a human
hair - or 100 times greater magnification than the lander's
optical microscope.
Until now, the spacecraft's optical microscope had held the
record for producing the most highly magnified images from
another planet.
"This is proof of the microscope's potential," Staufer
said. "We are now ready to start doing scientific experiments
that will add a new dimension to measurements being made by
other Phoenix lander instruments."
Earlier this month, Nasa said Phoenix had made the surprise
discovery of a sometimes toxic chemical, perchlorate, on the
surface of Mars.
Scientists were working to confirm the presence of the
chemical and rule out contamination by the spacecraft.
The agency has extended the Phoenix mission by five weeks,
adding about $2m to the $420m cost of landing
Phoenix on Mars for what was a scheduled three-month mission.