Europe plans large lunar lander

Europe is pressing ahead with plans to send a sophisticated, unmanned spacecraft to the surface of the Moon.

EADS Astrium has been awarded a 6.5m-euro contract by the European Space Agency (Esa) to do further detailed design work on the mission.

The 700-800kg robot would be aimed at the lunar south pole, using automated systems to guide itself into a gentle, precision landing.

Once down, it would release a small rover to trundle across the surface.

"The lander will have a set of scientific instruments onboard but the science will be geared towards human exploration," said Simonetta Di Pippo, the director of human spaceflight at Esa.

"We will be looking for minerals and, hopefully, water in the soil, to see if we can prepare for a sustainable presence on the surface of the Moon," she told BBC News.

Recent spacecraft observations have indicated that some polar craters on the Moon probably hide vast reserves of ice deep in their shadows.

The new study is being led by the German division of EADS Astrium.

Michael Menking from the company observed: "This is an important technology project. For sure, it's dedicated to the Moon but if you can make a soft, precision landing on the lunar surface you can also do it on other planetary bodies as well."

Self-selection

The feasibility work conducted in industry, known as a Phase B1 study, will elaborate the lander's key specifications, and initiate some component development and testing.

These investigations will inform the fully costed mission proposal (likely to come out at several hundred million euros), which will go before Europe's space ministers for final approval in 2012.

If the politicians like the concept and decide to fund it, the robot could leave Earth on a Soyuz rocket before the decade's end.

The mission would build upon the experience gained from Europe's highly successful Automated Transfer Vehicle (ATV), which resupplies the International Space Station (ISS).

Once in orbit, this 20-tonne freighter is capable of finding its own way to the platform using advanced navigation and sensor technologies.

In a similar vein, the Moon lander would have to take itself to a specific location, scan the area for slopes and boulders, and then pick out a safe place to put down.

"You need to have hazard-avoidance," said Bruno Gardini, who heads the Esa department in which the lunar lander project is embedded.

"During the descent, you have to keep targeting two or three different landing sites, and so you have to keep the algorithm available which is a very heavy load on the onboard processor. You need to be ready to switch from one site to another to select the one that has lowest risk."

Astronaut health

The spacecraft would be targeted at the lunar south pole because it has locations that enjoy extended sunlight. This is necessary because Europe does not possess the radioisotope space technology capable of generating the power and heat needed by robots to survive long periods of darkness.

One possible landing site already under discussion is a ridge close to Shackleton Crater where the Sun stays above the horizon for months on end. Solar panel and battery technology should be sufficient to sustain the robot at such a location.

Europe's ATV has demonstrated a high degree of automation at the space station

"Depending on the illumination pattern, we would hope to have a mission lasting several months, up to half a year," explained Richard Fisackerly from Esa's project team.

"The patterns we're looking at actually don't consider continuous illumination, but we should be able to tolerate very short periods of darkness which may be brought about by obstacles on the horizon."

As well as looking for any local resources that could be used by future human explorers, the lander's instruments would also assess the lunar environment to understand the risks it could pose to astronauts, said Esa project team-member James Carpenter.

"These have been identified as radiation and its effects on human physiology; and the lunar dust environment - both in terms of the physics of the behaviour of the lunar dust and the way it will interact with the systems that are on the surface, but also in terms of the potential health effects of lunar dust when it comes into contact with humans," he told BBC News.

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