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A New Zealand scientist has discovered a hazardous new obstacle to the US space programme's plan to return to the moon in 2020 - moon dust is bad for astronauts' lungs.
Moon dust can penetrate deep into the lungs, posing potentially great risks to astronauts with the planned resumption of lunar landings, says the scientist, who has studied astronauts' airways.
Dr Kim Prisk, a graduate of Canterbury and Otago universities, said yesterday that on the relatively short lunar visits of the 1960s and 1970s, moon dust was not a problem.
But now the US planned to return to the moon by 2020, eventually leaving astronauts there for up to six months at a time, it was proving to be a challenge.
Research was under way to find out how much dust astronauts were likely to inhale and where it would lodge, Dr Prisk said.
"There's a lot of interest with Nasa in lunar dust. It's extremely fine, extremely abrasive and has some characteristics that I think make it fairly toxic."
Dr Prisk said Apollo 17 astronaut Jack Schmitt had reported the effects of moon dust after his 1972 stay on the lunar surface.
"He said when you took your helmet off in the lunar module you got an instant burning sensation in your nose, not unlike the cordite smell when you fire a gun or light a match."
Gravity on the moon was one-sixth of that on Earth, which meant the tiny dust particles would stay suspended for longer.
Engineers were investigating ways of getting rid of the dust.
Dr Prisk is a pulmonary physiologist visiting Auckland from the University of California's San Diego campus to address the Thoracic Society and Scientific Respiratory Society conference.