3 July 2013 14:35

Space vehicles on the moon risk being covered in lunar dust say researchers.

Space agencies around the world have plans to continue the exploration of the Moon in the next two decades, with ever more sophisticated robots paving the way for astronauts to walk on the lunar surface once again.

A major problem is the dust found on the lunar surface, material that is abrasive, sticky and unhealthy to breathe, potentially fatally compromising an astronaut’s life support system.

According to Apollo Astronaut Gene Cernon, lunar dust poses the greatest barrier for operation on the moon.

"I think dust is probably one of our greatest inhibitors to nominal operation on the moon. I think we can overcome other physiological or physical or mechanical problems except dust."

Now an Anglo-French team of scientists have modelled how this dust will affect any rover vehicles travelling across the surface. They find a serious risk that rovers that move around sunrise and sunset could be engulfed in dust.

Professor Farideh Honary from Lancaster University, who was Vice President of the Royal Astronomical Society from 2011 to 2013, presented the new findings at the National Astronomy Meeting in St Andrews.

She believes this has implications for rover design: “On most of the lunar surface a rover would experience roughly 14 days of sunlight followed by 14 days of darkness, so the transition between the two would last a long time by terrestrial standards. Engineers really do need to think about this – one solution might be to build a dome-shaped rover so the dust simply falls to the ground.”

Professor Honary presented a study of the simulated motion of lunar dust near a rover, part of a joint project with ONERA in France to study dusty environments where electrical charging has a strong effect.

Simulations were made for two different lunar regions, the boundary between night and day (terminator) where the sun would either be rising or setting and the region experiencing full daylight.

The rover vehicle was modelled as a large rectangular box placed one metre above a simulation of the lunar surface. The terminator simulation began with a region void of dust which was later filled by lunar dust particles.

The scientists found that dust particles travel upwards above the height of the rover, but results suggest that they move in different directions.

On the dayside the particles are pushed outwards and on the terminator the dust travels upwards and inwards above the rover, regrouping in the vacuum above it. The results suggest that a structure such as a rover might collect a significant quantity of dust over time and that this would happen more quickly around sunrise and sunset.

In the 1960s and 1970s the United States and Soviet Union sent a series of robotic (Surveyor and Luna) and crewed missions (Apollo) to land on the Moon. These gave contemporary scientists a bank of data on the lunar environment including dust.

The major issues associated with it are abrasiveness, adherence to clothing and equipment, visibility reduction particularly during landing and the effect on human health of breathing in the dust particles.