Space Experts Prepare for Martian Land Grab

July 8, 2008 — -- Space experts will meet in France later this week to thrash out plans for an ambitious robotic spacecraft mission to return rocks from Mars to Earth – arguably the most ambitious interplanetary adventure ever attempted.

"This has been the holy grail for Mars scientists for a very long time," says David Parker of the British National Space Centre in London, UK. "We think it is doable, but it is going to take international collaboration and a lot of hard work to make it happen."

Mars is a hub of robotic activity, with NASA's Phoenix lander currently digging there and future landers such as the Mars Science Laboratory and ExoMars in the pipeline.

But no mission has ever returned Martian rocks to Earth, something that scientists consider essential to understanding the history of Mars and whether it ever hosted life.

Accurate Ages

One report previously identified 55 pressing studies to do on Mars. More than half of them could be only answered with a high degree of accuracy by a sample-return mission, while 13 of them could only be done at all by bringing rocks back to Earth.

Earth-based lab tests are essential for accurately assessing the abundances of different isotopes and trace elements, as well as identifying ancient life in the form of nanofossils.

With samples on Earth, scientists can double-check conclusions with a battery of different tests in labs around the world. Landers that look for life on Mars have the drawback that you have to guess the right chemical tests in advance; with rocks in the lab, scientists can change their tack as information unfolds.

Scientists also need to study Martian rocks in Earth-based labs to accurately determine their ages.

Heavy Loads

"You need large-scale lab equipment that you can't credibly take to the Martian surface," says Parker, chairman of the International Mars Exploration Working Group (IMEWG), which was set up in 1993 as a forum to discuss Mars exploration strategies.

Last year, IMEWG asked a committee of scientists and engineers called IMARS (International Mars Architecture for Return of Samples) to draw up draft plans for a sample-return mission. They will discuss their progress on Wednesday at a meeting in Paris.