Comments on Next Big Future: Solar Wind Electric Sail Propulsion planning test...

bw, By colonization ships are you referring to lar...

2008-06-04T22:46:00.000-07:00

bw, By colonization ships are you referring to large ships carrying adults or to potentially much smaller craft carrying microscopic cells? Would a craft carrying:
- cells,
- a small nuclear system to melt a habitat into ice,
- a small system to produce O2, water, food, and electricity,
- and perhaps a light android for childrearing
be at a mass requiring nuclear fusion, or would solar electric sail produce enough acceleration to get such mass to Alpha Centauri in 1,000 years or so. Remember that the components can be launched separately.

The solar electric sail is only for smaller object...

2008-05-27T14:24:00.000-07:00

The solar electric sail is only for smaller objects. It has problems scaling so it would be useful for big colonization ships.

Colonization ships would need nuclear propulsion like the Orion style external pulsed propulsion or a propulsion using IEC fusion. A nearer term vehicle could perform a close gravity slingshot of the sun (within 2 solar diameters). Near term technology can get such a ship up to 1-10% of the speed of light.

Solar wind = approx 1,000,000 km/hrAlpha Centauri ...

2008-05-26T17:58:00.000-07:00

Solar wind = approx 1,000,000 km/hr

Alpha Centauri = 41,500,000,000,000 km = 4.15 x 10^13 km

Therefore Alpha Centauri is:
- 473 years away at solar wind speeds.

473 years is too much time for a robotic science discovery mission. But not necessarily for a "preserving humanity" mission. Embryos might be able to remain viable after being frozen for 473 years. Same with stem cells to produce a uterus and blood. Childrearing would be a technical and ethical challenge for sure.

But just in case we wipe ourselves out with nanotech, biotech, a stable black hole, or AI then wouldn't it be nice to have such a craft heading to Alpha Centauri?

there is raw material in space for making fuel.Met...

2008-04-25T21:32:00.000-07:00

there is raw material in space for making fuel.

Methane based fuels can be made
http://www.space.com/adastra/adastra_tumlinson_060130.html

in-situ resource utilization

http://www.space.com/businesstechnology/technology/space_resources_031114.html

Off-world resources can be transformed into oxygen, propellant, water, as well as used for construction purposes and to energize power stations.

http://en.wikipedia.org/wiki/In-Situ_Resource_Utilization

Mining asteroids
http://en.wikipedia.org/wiki/Asteroid_mining#Mining

http://www.spacefuture.com/archive/the_technical_and_economic_feasibility_of_mining_the_near_earth_asteriods.shtml

The natural resources in space include metallic nickel-iron alloy, silicate minerals, hydrated minerals, bituminous material, and various volatiles, including water, ammonia, carbon dioxide, methane, and others. These have all been identified either in meteorites, or spectroscopically in asteroids and comets.

Because the electric space sail uses no propellant itself they can just keep making as many robotic trips as they can until their parts wear out.

"in-situ fuel making at high Earth orbit"I don't u...

2008-04-25T16:18:00.000-07:00

"in-situ fuel making at high Earth orbit"

I don't understand - would that be collecting H3 from the solar wind?

great story, regardless

I just can't seem to shake this picture in my mind...

2008-04-25T13:47:00.000-07:00

I just can't seem to shake this picture in my mind of thousands of these things plying the solar system - it almost sounds too good to be true!

Thanks for this post and the links. I have a gut i...

2008-04-21T06:54:00.000-07:00

Thanks for this post and the links. I have a gut instinct this is going to be a huge development in space travel.