Moon dust becomes eco hazard to astronauts due to Sun’s elevationApril 18th, 2009 - 12:50 pm ICT by ANI
Washington, April 18 (ANI): A new study has revealed that the Moon dust, which causes hazards like ruining scientific experiments and endangering astronauts’ health, is influenced by the Sun’s elevation.
Lunar dust has long been described as the No. 1 environmental hazard on the Moon.
It causes miscellaneous havoc: from destroying scientific equipment deployed on the lunar surface, to creating blinding dust clouds that interfere with lunar landings.
It also may be a health hazard to space travelers, since dust clinging to space suits detaches when astronauts reenter their lunar module.
It then floats free in zero gravity, ready to be inhaled, during the 3-day journey back to Earth.
Now, a study reveals that forces compelling lunar dust to cling to surfaces, change during the lunar day with the elevation of the sun.
The study analyzes the interactions on the Moon among electrostatic adhesive forces, the angle of incidence of the sun’s rays, and lunar gravity.
It concludes that the stickiness of lunar dust on a vertical surface changes as the sun moves higher in the sky, eventually allowing the very weak lunar gravity to pull the dust off.
“Before you can manage the dust, you have to understand what makes it sticky,” said Brian O’Brien, the sole author of the study.
He used data from the matchbox-sized Dust Detector Experiments deployed on the Moon’s surface in 1969 during the Apollo 11 and Apollo 12 missions.
O’Brien analyzed the behavior of dust on horizontal and vertical solar cells in one of the Apollo dust-detecting experiments.
On the first morning of the experiment, the lunar module - 130 meters (426 feet) away from the dust detector - took off from the Moon’s surface.
The blast of exhaust gases completely cleansed a dusty horizontal solar cell, because it was illuminated only by weak early-morning light and thus the adhesive force of dust was faint.
But, only half the dust covering the vertical cell was removed by the blast, because its surface faced east - into more intense sunlight- and thus the sticky forces were stronger.
O’Brien found that later, as the sun rose and the angle of incidence of the sun’s rays on the dusty vertical surface facing east decreased, the electrostatic forces on the vertical cell weakened.
The tipping point was reached when the sun was at an angle of about 45 degrees.
Then, the pull of lunar gravity counteracted the adhesive forces and made the dust start falling off. All dust had fallen by lunar night.
“These are the first measurements of the collapse of the cohesive forces that make lunar dust so sticky,” O’Brien said. (ANI)
- Scientist unravels moon dust mystery - Apr 18, 2009
- Moon dust stickiness depends on solar elevation angle - Jun 01, 2009
- Moon craters may be electrified - May 24, 2010
- Frog feet could solve sticky medical problems - Jul 03, 2011
- Moon dust could be toxic to humans - Jul 15, 2012
- Lunar polar craters likely to be live with electricity - Apr 19, 2010
- Gecko's feet inspire unique wall hugging device - Feb 17, 2012
- Moon may have as much water as Earth has - May 27, 2011
- Moon has liquid core just like Earth - Jan 08, 2011
- NASA's LRO releases final set of data from mission's exploration phase - Mar 16, 2011
- Nanoparticles can solve mystery of Moon's topsoil - Jun 13, 2012
- Sleep problems may cause kids to become aggressive - Jun 01, 2011
- Moon map reveals titanium treasure trove - Oct 16, 2011
- Moon's surface contains silver: Scientists - Oct 22, 2010
- NASA spacecraft gets its first look at Apollo moon landing sites - Jul 18, 2009
Tags: adhesive force, adhesive forces, angle of incidence, apollo 11, apollo 12, dust clouds, dust detector, environmental hazard, exhaust gases, lunar day, lunar dust, lunar gravity, lunar landings, lunar module, moon dust, s rays, solar cells, space suits, space travelers, vertical surface