"A photon smacks the sail and reflects off with lower energy. The sail moves away from the bounced photon like a struck punching bag. The same force blows comet tails away from the Sun...Thomas Gold, physics professor emeritus at Cornell University in New York disagrees. He says that the sail is a perfect mirror and, as such, will reflect the photon with no loss of energy. No loss of energy on the photon’s part means no gain for the sail. The sail won’t move."

http://www.wonderquest.com/solar-sail-chicks-light-speed.htm

If NASA is investing money into developing this I can see them investing money into developing a solar sail able to convert energy for an ion engine. Maybe it'll take another 20 years, industial manufacturing of nanotechnology, and carbonfiber rope has a long way to go, but I think it'll happen. Hey, if we can spend 250 billion on the Joint Strike Fighter, we might be able to scrounge up a few hundred million to send a solar sail out of the solar system. I mean what would have happened if Christopher Columbus hadn't had any funding? America might now be the largest province of China. Governments have a vested interest in exploring our solar system and the technology that can get us there.

Just for the record, solar sails aren't pushed by the solar wind, but are pushed by the light of the sun. This push is so gentle that the craft needs to be as light as possible to get significant acceleration.

-Suneet

Here are some relevant websites:

Glenn Research Center

New NASA technology stuff

Solar Sail Paper

Just for the record. Solar sails may not work. Magnetic sails might though, and they use solar wind for propulsion.

Here are the websites for the companies whose two designs NASA is currently testing: L'Garde, Inc. and SRS Technologies

Solar sails may not work? What's that assertion?

My opinion is that they do work, are way better than chemical propulsion for many missions, and should have been developed a long time ago.

Even with a reasonable thickness (like 5µm - for comparison, blanket used to wrap wounded people is under 20µm thick), a craft with a solar sail would go to a polar Sun orbit within 1 year, as opposed to half a decade for Galileo.

So it's certainly the engineering headache worth.

Wow, this thread hasn't had a post for 3 1/2 years and now this - lol.

I think the original reason why it was mentioned it would not work is for interstellar travel between the stars. It would be like taking the sun from our solar system, which one of the thousands of star then would have enough umph to use a solar sail then?

Answer: None

G'day .001

You can talk about anything and everything.

As for solar sail and solar panel, both can be incorporated into one.

Intergalactic black hole orbiting near to the Sun would be dangerous gravitational sail for solar system. The Sun’s orbit could be changed and interstellar traveling would be finished by the hit to another star or to the pirate black hole. Similar event forms huge nebula. For example: Eagle nebula, Elephant nebula.

My point is that the forum has loss support of founders (scientist of mainstream). The founders don’t want to spent money for internet as well as for moderators. The forum has already proved that mainstream direction is not true. Now the forum as well as astronomy and cosmology are in the crisis.
I want to say that, the BB theory, accretion theory and other wrong theories meet to the great enemy in the forum: The Cosmogeological theory -

http://www.cosmogeology.ge/BOOK%20BY%20AUTHOR.htm

I’m very sorry for forum but - TRUTH IS VICTORIOUS!!!
There is already began new epoch; epoch of Cosmogeological theory!