James Randerson, science correspondent
Wednesday May 10, 2006
The Guardian
From the first two failed Soviet missions in October 1960 to Britain’s ill-fated Beagle 2 that crash-landed on Christmas Day 2003, Mars has a history of devouring space missions for breakfast.
But despite its cursed reputation, British scientists are vying for funding to unlock the secrets of the red planet.
This summer three British projects will compete for money from the European Space Agency to send an unmanned mission into space to garner data on the planet that has fascinated astronomers for decades because of its potential to harbour rudimentary life.
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The first enterprise is designed to tackle Mars’s mysterious moons Deimos and Phobos – named after the sons of Mars, the Greek god of war. Phobos is also Greek for fear. “All the focus has been on Mars itself. We don’t know much about these two,” said Professor John Zarnecki of the Open University. “One big question is their origin. Where the hell did they come from? Were they formed in orbit around Mars or are they captured asteroids?”
The mission’s 310kg (50 stone) pool table-sized probe would take 20 months to reach Deimos before orbiting the moon for a further month while analysing its structure and mapping the surface. It would then switch orbit to Phobos and could send down a lander to carry out more detailed measurements. “Technically this is quite demanding. You’ve got to go there and get in orbit around them or orbit around Mars so that you come close to the moons,” Prof Zarnecki said.
The second option is to send four satellites launched by the same rocket to spy on the Martian climate. The 120kg probes would make the journey to Mars together but then split up and orbit separately 1,000km from the surface. The probes would compare temperature, atmospheric composition and wind speed at different points in the atmosphere.
The final scheme is aimed at answering the question of whether Mars supports life now or has done so in the past. To get close to this, scientists want to know the extent of water on Mars. Today Mars’s surface is bitterly cold and dry, but in its younger days the planet was warmer and wetter. Previous missions have identified channels and sedimentary deposits left by running water and there is evidence for ice at the poles. There is a slim chance that Martian microbes might still live underground.
The proposed mission would investigate the extent of ice under the surface by firing four penetrators into the rock – two near the poles and two near the equator. These would beam results to the orbiter. The 800kg cone-shaped probe is designed to fit neatly into the nose of an Ariane 5 rocket – ESA’s favourite launch vehicle. This would mean the ice mission could piggyback on another launch, cutting costs dramatically.
The projects face competition from other European countries but because the ideas have already been developed, there is a sense that Britain may have the upper hand. “Having some ideas already worked up and on the shelf will put the UK scientists in a good position,” said David Parker of the British National Space Centre, which funded the research.
If one of the three projects wins European favour, a British team could have it up and running as early as 2008. Each of the spacecraft has been described as “off the wall” by Prof Zarnecki, who led the development team. He also was part of the ill-fated Beagle 2 mission in 2003. They all use an exotic propulsion system and are designed to be lightweight.
In theory, Britain could go it alone with one of the cut-price missions. “Technologically I think we have the capability to do missions of that order,” Mr Parker said. But he added they would only be launched in partnership with ESA or Nasa.
The missions, which are described in a study to be published in Acta Astronautica, were conceived to fit into ESA’s Aurora exploration programme, but could now be funded under the agency’s Cosmic Visions programme, which will invite proposals in the summer.
Being cheap should help their cause. “These are relatively low cost in terms of space research,” Prof Zarnecki said. Unlike a conventional Mars mission that would cost £500m or more, the proposed missions should cost less than £150m each.
He said it was important to be ambitious: “In the space business you start with these slightly crazy ideas. Some turn out to be too crazy and you put them back on the shelf, [for] others within 10 years what was science fiction becomes science fact.”
· Space scientists call it the curse of Mars. Of 37 missions to map, explore and land on the planet, 18 have succeeded. And some of those stretch the definition of success.
· The first probe to send back images of the planet (21 in total) was the US Mariner 4, launched in 1964. But the planet had to wait until 1971 for a touchdown. The Soviet Mars 3 lander got to the surface, but only managed to send 20 seconds of data before failing.
· The US Viking missions that touched down in 1976 were the first to send extensive data.
· We’re getting better at overcoming the curse, though. The European Space Agency’s Mars Express, which carried Beagle 2, is still orbiting the planet along with three other US missions.
· Nasa’s superbly successful rovers Spirit and Opportunity – which landed in January 2004 – are still trundling around sending back data. They were only built to last 90 days.
Updated/maj. 11-05-2006
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