The Flight of the Solar Sail

N3wsByt3 writes "After months of uncertainty, the final verdict has fallen: The Planetary Society has reveiled that it will launch its Cosmos 1 on June 21. Cosmos 1 will be the first non-governmental spaceship that makes use of solar sails as main propulsion mechanism - it is pushed along by light particles from the Sun, instead of bringing its fuel along for the ride - which makes this a unique experiment in more then one way." This was supposed to have happened already, so here's hoping things get off the ground this time.

Comments

As opposed to...

[Vox Humana]

all the governmental solar sail spacecraft? WTF?

This seems silly

[Albinofrenchy]

Honestly the idea that because it doesn't carry fuel makes it easy to 'travel to the stars' is kinda stupid. For one thing, almost by definition you can't travel towards a star on this thing because as you approach it, it will start to slow down, and eventually stop.

The idea of using the suns energy is good, but maybe they should find a way to harness that energy so one could move the direction one pleases.

Re:This seems silly

[imsabbel]

Well, isnt slowing down and stopping exactly the thing you WANT when approaching the destination star? :)

But yes, its not that easy. And yeah, at least in earth orbit, solar wind dominates over photon pressure. Also, the interstellar medium would be a much too big drag factor.

Re:This seems silly

[rsynnott]

Actually, that's one of the nice things about it. Assuming the other star has the same solar wind as the original (which it probably won't) your spacecraft may actually come to a complete halt at the other star, which is what you want. A classic problem with interstellar travel is that not only do you need to carry fuel to accellerate you towards the objective, but to slow you once you get there as well.

Re:This seems silly

[ciroknight]

I'd say the most classic problem is interstellar travel itself; since our most far-out space craft are just now breaching what we know to be the end of our solar system, we have no idea about any of the dangers of interstellar travel. And my guess is that we won't for another two hundred or so years, once everything in our solar system has been "decently" explored and the technology exists to cheaply put things into space.

Besides, slowing down isn't as difficult as speeding up; use the slingshot effect in reverse. Steer around the orbits of other, high-mass planets, using their gravity wells to slow your momentum until it's possible to chemically control. That in combination with shedding weight (mass driver would probably have to be installed in front of the craft to soak up radiation/protect against high speed collisions) should help a great deal. But who knows. Cross a bridge when we get to it.

Re:This seems silly

[rsynnott]

If you're willing to go there REALLY slowly, then yes, this would work. The slingshot effect won't help much for very high velocities. Basically, for sensible, remotely useful interstellar travel, we'll have to wait for either some magic source of energy, or a Bussard ramjet, or some other magic thing. I'll be a while :)

Solar Sails

[DeadlyBanana]

so apparantly we have the technology to propel objects via sunlight... but we still cant make our cars to utilize a resource besides gasoline ( with a little hydrogen somestimes)?