The Planetary Society together with NASA are hoping a metalised Mylar sail, just 1/100th thickness of a sheet
of paper, will be pushed across space by the power of light photons. Not only might it be 'pushed',
but some believe that given enough time, it will eventually accelerate to speeds of thousands of miles an hour.
Could that be a theoretical dream?

What about the micro dust particles in space? Some of them not so micro.
A few years ago NASA asked for'home volunteers' to count the number of micro-particles that buried
themselves in a block of jelly that was flown in space.
There were thousands of micro particles found...I know, I was one of NASA's searchers. Manipulating bits of jelly in the USA, using my 'puter mouse in the UK.

Being a Mirror Sail, I wouldnt think a few hundred or more punctures thru the Mylar would have any effect upon its speed.
But prehaps there could be an Electrostatic effect...with particles eventually covering one or both sides of the Mylar film?
That would certainly slow the light-Sail.

Thomas Gold, the famous scientist (who proved that oil was formed deep within out Earth by rock eating Bacteria) Stated 'that a Light Sail could not work,' ...meaning fly. Stating 'Carnots' limit to the thermodynamic rule of pressure would prevent the Sail from flying in space.

We will have wait until Nov: 2010 to find out the truth.
When, next year 'The Planetary Society' put up a large Mylar sail to float 500 miles above the earth.

There have been at least six previous attempts to deploy Solar sails by other Countries. Russia X2, Japan x2, and the U.S X2.
None of them were a success, due to rocket failures or the incomplete unfurling of the Mylar sail.

http://www.wired.com/science/space/news/2005/05/67400

http://arxiv.org/html/physics/0306050


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"You will never find a real Human being - Even in a mirror." ....Mike Kremer.