Mason Inman - science journalist

15 April 2005, for Science

LONDON—More than 100 European scientists met last week in Birmingham, U.K., to define Aurora, a solar system exploration venture that faces a critical decision this year.

The workshop on 6 to 7 April began with one certainty: Europe wants its own Mars program.

The scientists endorsed a one-way robotic trip to Mars in 2011 and hashed out the types of instruments they want onboard to search for signs of life and study geology. They also backed a follow-on sample-return mission. But big issues remain to be settled, such as whether governments will pay, and how they will coordinate the work with an ambitious U.S. Mars program.

Aurora's head at the European Space Agency (ESA), Bruno Gardini, said at a press conference here that he was pleased with the workshop's outcome. "It has given us a very focused target," he said. Doug McCuistion, director of NASA's Mars Exploration Program, an observer at the workshop, agrees: "It's very important that they were able to narrow their options so they can go forward."

Three proposals were on the table at the outset. The scientists recommended plucking out elements of each and rolling them into one mission, as yet unnamed. One piece of heavy equipment made it onto their consensus wish list: a drill to take samples at a depth of up to 2 meters below Mars's oxidized surface. NASA does not have a drill on its agenda, McCuistion says. The scientists also recommended including a rover with sensors to look at ratios of isotopes for traces of past or present life, modeled after those on Beagle 2, the United Kingdom's ill-fated robot that went missing in December 2003 during its descent to Mars. The scientists also want to include a seismograph to detect possible "marsquakes" that could show that the planet is geologically active.

Before the plans get much more specific, ESA needs some of its member countries to pony up for the mission, which carries a price tag of €500 million ($650 million). ESA members make voluntary contributions to Aurora, described at its launch in 2001 as a search for signs of life beyond Earth and a start to crewed exploration of the solar system. By June, Aurora's staff will put together a more detailed plan for a complete funding review, in which countries will choose whether to pledge support to carry the 2011 project through to completion. The total budget is "a very challenging target," Gardini said. "We are trying very hard to get support from NASA to reduce the cost and risk of the mission." Canada, Japan, and Russia might also take part in the mission, he added.

European researchers see the 2011 mission as preparation for a much more ambitious round trip to return samples of Mars rock, soil, and atmosphere. Space scientist John Zarnecki of The Open University in the United Kingdom, a participant in the workshop, said the group recommended working toward such a mission in 2016, which would fit with NASA's timing for such a mission. "I think everyone hopes and expects that this is going to be a big international push with ESA, NASA, and possibly other agencies," Zarnecki says.

This work is designed to prepare for possible international crewed missions to Mars, which ESA hopes will begin around 2030. Gardini said the sample-return mission would be valuable practice in making the round trip. Aurora faces a big test in December, when ESA's governing council will vote on funding.