Shields up! Force fields could protect Mars missions

[n2doc]

28 July 2010 by Marcus Chown


Wernher von Braun, the rocket pioneer who created the Apollo programme, first thought about a magnetic shield for spacecraft in the 1960s. He eventually dismissed the idea because he thought it would require an impractically large magnet. He was wrong. "The physics is more subtle than those simple 'back of the envelope' calculations," Bamford says.

That subtlety has come to light through a series of discoveries made by roaming spacecraft. We initially thought that the only magnetospheres in the solar system belonged to bodies large enough to keep an iron core molten and churning. But it turns out that our solar system is littered with small but surprisingly powerful magnetic shields.

There seem to be several on the moon, for a start. The particles of the solar wind have gradually darkened most of the moon's surface, but lighter-coloured swirls are also visible at various points. In 1998, NASA's Lunar Prospector flew over one. The probe was skimming only 18 kilometres above the surface when its sensitive instruments indicated it had crossed through a region of bunched-up magnetic field lines and moved into a cavity where there was a sharp drop in the density of charged particles. It had entered a mini-magnetosphere that the solar wind's particles could not penetrate.

This field most probably arose when the heat from an asteroid impact melted the lunar surface. This would have created a plasma - a cloud of hot, ionised gas. Plasmas carry a magnetic field, and when the lunar surface resolidified, the rock would have preserved an imprint of the plasma's magnetism.

The field the Lunar Prospector found is a few hundred kilometres across and extends tens of kilometres out into space (Science, vol 281, p 1480). Most interesting of all is the protection this not particularly strong field seems to offer from the ravages of solar radiation, judging by the colour of the soil beneath the bubble (Planetary and Space Science, vol 56, p 941). "It's as if, for billions of years, the rock has been partially shielded from the chemical etching of the solar wind," says Bamford.


more

http://www.newscientist.com/article/mg20727701.300-shields-up-force-fields-could-protect-mars-missions.html

[1620rock]

1. Wow, great info. Thanks for posting.

[foxfeet]

2. The Fundies are plotting how to use this in chastity belts.

[derby378]

5. Sounds like a really ill-advised remake of DUNE

"The slow penis penetrates the shield!" :rofl:

[Greyskye]

3. Potential huge news for future manned space travel.

But can they make a good enough shield to survive major flares/solar storms? Looks like this will at the very least be a part of the solution.

Good stuff, thanks for sharing.

[txlibdem]

4. Short answer = yes

They're not going to generate the magnetic field with a lump of magnetic rock. It'll be an array of electromagnets.