Artist's concept of the Opportunity rover on the surface of Mars
Opportunity, NASA's other Mars rover, has tooled around the red planet for so long it's easy to forget it's still alive.
5,000 miles away from the limelight surrounding Curiosity's every move,
Opportunity this week quietly embarks on its tenth year of exploration
-- a sweet milestone since it was only tasked to work for three months.
is still going. Go figure," said mission deputy principal investigator
Ray Arvidson of Washington University in St. Louis.
it's not as snazzy as Curiosity, the most high-tech interplanetary
rover ever designed. It awed the world with its landing near the Martian
equator five months ago.
After so many years crater-hopping, Opportunity is showing its age:
It has an arthritic joint in its robotic arm and it drives mostly
backward due to a balky front wheel -- more annoyances than
For the past several months, it has been
parked on a clay-rich hill along the western rim of Endeavour Crater
that's unlike any scenery it encountered before. It plans to wrap up at
its current spot in the next several months and then drive south where
the terrain looks even riper for discoveries.
Long before Curiosity became everybody's favorite rover, Opportunity was the darling.
six-wheel, solar-powered rover parachuted to Eagle Crater in Mars'
southern hemisphere on Jan. 24, 2004, weeks after its twin Spirit landed
on the opposite side of the planet.
During the first
three months, there were frequent updates about the twin rovers' antics.
The world, it seemed, followed every trail, every rock touched and even
kept up with Spirit's health scare that it eventually recovered from.
immediately lived up to its name, touching down in an ancient lakebed
brimming with minerals that formed in the presence of water, a key
ingredient for life. After grinding into rocks and sifting through dirt,
Opportunity made one of the enduring finds on Mars: Signs abound of an
ancient environment that was warmer and wetter than today's dusty, cold
Spirit, on the other hand, landed in a less
interesting spot and had to drive some distance to find geologic
evidence of past water. After six productive years wheeling around, it
fell silent in 2010, forever stuck in Martian sand.
Opportunity went on to poke into four other craters, uncovering even more hints that water existed on Mars long ago.
rover "is not like a lander staring at the same real estate. We've gone
to different terrains, explored different geology and answered
different questions on Mars," said project manager John Callas of the
NASA Jet Propulsion Laboratory, which runs the $984 million project.
What's still unknown is whether Mars ever had the right environmental
conditions to support microscopic organisms -- something Curiosity is
trying to answer during its two-year mission. Besides water, it's
generally agreed that a power source like the sun and carbon-based
compounds are essential for life.
Unlike the flashier
Curiosity, armed with the latest tools, Opportunity is not equipped with
a carbon detector. Its latest crater destination, which it arrived at
last year after an epic three-year journey, contains sections rich in
clay deposits. Clays typically form in the presence of water and can be a
fine preserver of carbon material. But scientists will never know.
it enters its tenth year on Mars, Opportunity will continue studying
the chemical makeup and pinning down the ages of several interesting
rocks at its location for several more months before adding more mileage
to the 22 miles it has logged since landing.
As for the
hunt for carbon, all eyes are on Curiosity, set to drive later this year
to the base of a mountain where rock layers containing clay minerals
have been detected.
Callas, the JPL project manager, said
Curiosity has a long way to go to catch up with Opportunity, which has
nearly a decade head start on the Martian surface.
"Mars is big enough for more than two rovers to explore," he said.