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Concentration fluctuations for the mixture fluid sample on Earth (left) and aboard Foton-M3 (right).

Olivier Minster (Head of ESA's Physical Sciences Unit) commented: "It is a rare event when a space mission is able to confirm a theoretical prediction in such record time. These results are important because they are the first verification of the effects forecast a decade ago". And Professor David Cannell of the University of California at Santa Barbara (UCSB) said: The availability of these images from the spacecraft has enabled us to change what we are doing so that we can optimize the scientific return from the mission," said P. "We will also have many thousands of images to analyse back in our labs following the end of the mission. This will keep us busy for quite a while."

Static Electricity Could Short- circuit Moon Missions [From a press release from the Royal Astronomical Society]

M any people would get a charge out of standing on the Moon, but a little

extra electric charge could endanger the astronauts who visit it in the second half of the next decade. During this period, the Moon will pass through part of Earth's magnetosphere, causing static electricity to build up on the

lunar surface. This effect is reported by Mike Hapgood of the UK's Rutherford Appleton Laboratory in the journal Annales Geophysicae (published on 2 October 2007, in volume 25, pp. 2037-2044) and previously reported at the UK's Royal Astronomical Society National Astronomy Meeting in Preston, in April. The resulting charge could short-circuit electronics and affect the behaviour of lunar dust particles, which are fine enough to enter living quarters and even spacesuits.

The Moon may look serene as it hangs in the night sky, but its surface is a hostile and dangerous place. Temperatures in the darkened portions of the Moon plunge to -170°C, whereas those in the light climb ro as high as 100 °. As the Moon has no atmosphere to shield it, its surface is continually pelted with radiation from space. Mike Hapgood suggests that static electricity may also severely hamper future missions to the Moon. He points out that electrical charging is one of the less well known natural hazards of spaceflight. The lunar surface charges up roughly every 18 years because of changes in the orientation of the Moon's orbit. For a number of years during each peak, the orbit intersects the so-called plasma sheet - a thin region in the Earth's magnetosphere that contains many electrically- charged particles from the Sun. These particles

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crash into each other and charge the lunar surface, was witnessed by NASA's Lunar Prospector spacecraft in 1998, during the last solar maximum. A geometric analysis of the Moon's orbital changes shows that electrostatic charging of the lunar surface was low during the Apollo era, but it will be high in the second half of the next decade, when various space agencies are planning to send robots and people to the Moon. That could be a real hazard to astronauts as well as to sensitive electronics, because electrostatically-charged dust particles would tend to stick more easily to any surface, so they are harder to get rid of.

ESA's chief scientist Bernard Foing opined that the hazard must be taken seriously, ccommenting that "it would be useful to develop precursor monitors that could measure the electrostatic properties of Moon dust". However, Rolf de Groot of the SRON Netherlands institute for Space Research in Utrecht believes the problem is manageable, at least for crewless missions. He commented: "Of course, we'll have to make sure lunar surface charging doesn't pose a health threat to astronauts so designers of moonsuits will have to take note".

A return to the Moon? Charged dust could be a problem. Image of Crater Plaskett and its companions taken by the SMART-1 spacecraft. [Courtesy: ESA/Space-X (Space Exploration Institute).]

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