Melbourne: A return to the Moon could be hampered by dust, a poorly-understood threat to machines and people alike, it has been revealed.
Simulations by scientists in Britain and France show that in key zones of Earth`s satellite, dust kicked up by a landing or exploration gains an electrostatic force that briefly overcomes lunar gravity, a space conference heard.
As a result, the dust lingers high above the surface, presenting a thin grey cloud of fine, sticky, abrasive particles that hamper visibility, coat solar panels and threaten moving parts, a news website reported.
Some kinds of lunar dust are laden with iron, presenting a toxicity risk for humans if breathed in, they said.
Farideh Honary, a professor at the University of Lancaster, northwestern England, said lunar dust was already identified as a potential hazard by returning Apollo astronauts.
But only now, with mounting interest in a return to the Moon, were scientists taking a closer look, she said.
"We need to study the dust in much more detail and to do more measurements before (sending) manned missions," she said by phone.
In a computer simulation presented at the annual conference in Edinburgh of Britain`s Royal Astronomical Society (RAS), Honary said dust did not behave uniformly around the Moon.
What makes the dust levitate and cling is a force caused by electrostatic charge.
Exposure to ultraviolet rays in sunlight drives out electrons and gives the dust a positive charge. But at night-time or in shadow, the torrent of particles spewed out from the Sun charges the dust with electrons, giving it a negative charge.
The dust movement occurs most in areas where the Sun is either rising or setting, and dust particles of opposite charges that are disturbed get pulled towards each other, floating in a haze.