Japan Launches World's First Solar Sail

[MadScientist]

Don't forget they also have to escape the "Strange Barrier Force" thing that was detected acting on Voyager.

 

I don't suppose anyone has a link for info on this "strange barrier force" thing??

All I can find are too many references to Star Trek Voyager.

 

 

I'm going to assume a solar sailed powered vehicle can escape this STB. Some have asked about how effective the photons would be once it reached deep space.

I don't think it needs to be effective at all. Once it's free of our systems gravity it'll continue travelling until it hits something. I don't think it even needs to keep moving...

 

Plot a course out of our system to a point outside our system that another system will pass over. A bit like throwing a rock off our planet, waiting 365 days then picking it up again.

 

 

Another thing that I can't help wondering about.

How fast are these solar sail vehicles likely to travel??

I'm just curious as to whether they'll eventually overtake Voyager itself.

[Sayonara]

Sorry, it was the Pioneer probes, not Voyager:

http://news.bbc.co.uk/1/hi/sci/tech/1332368.stm

 

I'm not sure if Voyager has reached the bow shock of the solar system yet:

http://news.bbc.co.uk/1/hi/sci/tech/3245677.stm

[swansont]

Just because the solar cells absorb the photons doesn't alter the fact that the momentum of those photons has been transfered to the craft. And not all of the crafts sail will be made up of solar cells anyway.

 

Think of the photons as cannon balls fired at you. If they hit you' date=' it doesn't matter if they bounce off or if you catch them, they have still transfered momentum to you, pushing you away. The photons are like a constant stream of cannon balls fired at the craft, pushing it away.[/quote']

 

Right. But you do better by a factor of 2 if you reflect the photon rather than absorb it.

[gene]

may i know what feature of the solar cell causes the photons to be reflected?

[Martin]

may i know what feature of the solar cell causes the photons to be reflected?

 

it is not made of solar cell

it is mirror

 

like a thin sheet of plastic, vapor-coated with metal to

make it shiny

 

any time you shine light on any mirror, it gives the mirror

a gentle push

 

the push is too weak, mostly, for you to see the mirror move

[swansont]

may i know what feature of the solar cell causes the photons to be reflected?

 

I missed that - some people are talking about solar cells, and some are talking about solar sails. Different items. I was thinking "sails" when I responded. But all objects reflect light to a certain degree, though presumably solar cells are optimized for absorption, and sails for reflection.