[X] My Assistant

[Marslauncher]

Just got tipped off to this story

http://news.scotsman.com/scitech.cfm?id=16902006

Here is the paper

http://www.uibk.ac.at/c/cb/cb26/heim/theor...sicsaip2005.pdf


They could feasibly have a prototype within 5 years!!!

Happy New Year indeed everyone.

[Steffen]

As Carl Sagan always said ' 99% of the speed of light would be fine '

[dilo]

Did someone noticed this article?
http://www.nasa.gov/mission_pages/explorat..._spaceship.html

If is serious (and it seems) I'm really disappointed; we know that antimatter is the best space fuel, but only theorically and I was convinced that should remain a SF matter for many, many years... at least, until we colonize solar system and start to think to interstellar missions!
Now they want to use for a Mars manned mission; idea is very intriguing, but seems a little bit crazy too...
We never created large amounts of antimatter (and 0.01g is a "large" amount), efficieny prodution is very low and safety issues would be huge during production, storage, launch and mission. I think a moon base should be best place to make antimatter, while on Earth should be forbidden.
I'm especially scared by possible military and terroristic use of it (consider that you can make a megaton bomb with only 1 gram of antimatter)... in fact, if you go at the positronics site, they talks about "national defense and security" applications and "portable/compact storage devices" too!
Very scaring to me!
I would know other impressions.

[Guest_Richard Trigaux_*]

Did someone noticed this article?
http://www.nasa.gov/mission_pages/explorat..._spaceship.html

(snip)
I would know other impressions.

Yes, the simple figure 0.01gr of positrons = 1 trip to Mars is very impressive!

But there are some drawbacks...

-0.01 gr of positrons are a huge electrical charge, and they repell each other with forces of millions of tons, far beyond any magnetic force we can do
-the magnetic confinment would weight thousands tons
-the cost would be much higher than with conventionnal rockets
-the crew would need a heavy shield
-etc


So this sounds still VERY VERY speculative. We shall not see soon positronic spaceships... nor positronic bombs.

[dilo]

So this sounds still VERY VERY speculative. We shall not see soon positronic spaceships... nor positronic bombs.

...nor positronic brains!
(do you know Data character?)

[Bob Shaw]

About the only vaguely feasible fast rocket system I've come across is VASIMR, and I was thinking about it earlier today not so much with regard to pushing spacecraft about as to moving asteroids. I'm sure everyone has heard of the innovative 'gravitational tractor' concept, but I wondered whether it would be possible to create some sort of localised magnetospheric 'parachute' on the surface of an asteroid which might either repel charged particles or attract them. If you had a solar-powered system which charged capacitors then let go that stored energy in a series of pulses as the asteroid rotated then perhaps it might be possible to modify the orbit of a small body, even an Itokawa-class rock-pile.

http://en.wikipedia.org/wiki/Variable_spec...toplasma_rocket

Any thoughts?

Bob Shaw

Attached File(s)

 VASIMR_TP_1995_3539.pdf ( 270.04K ) Number of downloads: 441