The Apollo Moon missions of 1969-1972 all share a dirty secret. “The major issue the Apollo astronauts pointed out was dust, dust, dust,” says Professor Larry Taylor, Director of the Planetary Geosciences Institute at the University of Tennessee. Fine as flour and rough as sandpaper, Moon dust caused ‘lunar hay fever,’ problems with space suits, and dust storms in the crew cabin upon returning to space. Taylor and other scientists will present their research on lunar dust at the “Living on a Dusty Moon” session on Thursday, 9 October 2008, at the Joint Meeting of the Geological Society of America (GSA), Soil Science Society of America (SSSA), American Society of Agronomy (ASA), Crop Science Society of America (CSSA), and Gulf Coast Association of Geological Societies (GCAGS) in Houston, Texas, USA.* NASA will use these findings to plan a safer manned mission to the Moon in 2018. Taylor will also deliver a Pardee Keynote Session talk on Sunday, 5 October 2008 entitled “Formation and Evolution of Lunar Soil from An Apollo Perspective.”
The trouble with moon dust stems from the strange properties of lunar soil. The powdery grey dirt is formed by micrometeorite impacts which pulverize local rocks into fine particles. The energy from these collisions melts the dirt into vapor that cools and condenses on soil particles, coating them in a glassy shell.
These particles can wreak havoc on space suits and other equipment. During the Apollo 17 mission, for example, crewmembers Harrison “Jack” Schmitt and Gene Cernan had trouble moving their arms during moonwalks because dust had gummed up the joints. “The dust was so abrasive that it actually wore through three layers of Kevlar-like material on Jack’s boot,” Taylor says.
To make matters worse, lunar dust suffers from a terrible case of static cling. UV rays drive electrons out of lunar dust by day, while the solar wind bombards it with electrons by night. Cleaning the resulting charged particles with wet-wipes only makes them cling harder to camera lenses and helmet visors. Mian Abbas of the National Space Science and Technology Center in Huntsville, Alabama, will discuss electrostatic charging on the moon and how dust circulates in lunar skies. …
Lunar dust is extremely abrasive — and unavoidable — as astronauts quickly learned during the Apollo missions of the 1960s and ’70s. Within hours, the dust covered the astronauts’ spacesuits and equipment, scratching lenses and corroding seals. Fortunately for the astronauts, their contact with lunar dust was short enough that it didn’t cause any major problems. But explorers living on a moon base for weeks or even months at a time are not likely to get away so clean.
Under prolonged exposure, the explorers would be at risk for everything from mechanical failures in spacesuits and airlocks to lung disease, said researchers last week at a NASA workshop focused on the issue. “Dust is the No. 1 environmental problem on the moon,” said Apollo 17 astronaut Harrison Schmitt, who reported having a severe allergic reaction to moon dust during his mission in 1972.
“We need to understand what the (biological) effects are, because there’s always the possibility that engineering might fail.” Moon dust is much more jagged than dust on Earth because there’s no water or wind on the moon to toss it around and grind down its edges. It’s created when meteorites, cosmic rays and solar winds slam into the moon, turning its rocks into powdery topsoil. The Apollo astronauts couldn’t help but get covered in the stuff as they struggled to stay upright on the moon’s surface, where the force of gravity is one-sixth of that on Earth. Later, they tracked the dust back into their space capsules and inhaled it when they took off their helmets. “When you go weightless again, it shook up from the floorboards,” said Schmitt. “It smelled like spent gunpowder.”
Though no astronauts have reported coming down with any illnesses due to their contact with lunar dust — save for Schmitt’s brief allergic reaction — samples brought back to Earth have some peculiar properties that worry researchers. For one, some of the dust particles are only a few microns wide. This makes it easy for the particles to get deep into the lungs and stay there. Scientists worry that this could eventually lead to fatal lung diseases similar to silicosis. Also, the dust is littered with bonded shards of glass and minerals known as agglutinates, which were formed in the heat of meteorite impacts. Agglutinates have not been found on Earth, and scientists worry that the human body may not be able to expel them efficiently if inhaled. “They have sharp angles, with arms that stick out and little hooks,” said David McKay, chief scientist for astrobiology at NASA’s Johnson Space Center. “It’s like Velcro.” –
Now we know how the moon smells, but I wonder how they cleaned the camera lenses.