Posted on 12/01/2004 4:49:17 PM PST by KevinDavis
SEATTLE – Sitting in the cramped coach section of a transcontinental airliner for five or six hours can be trying enough. But consider NASA's "reference mission" to Mars. Astronauts will be cooped up in their craft for up to six months each way as they travel to and from the Red Planet.
Robert Winglee and his colleagues would like to give these future explorers a break. Inspired by the sun's influence on Earth, the team is developing a unique approach to space propulsion. The craft it envisions hurtles through space on sails made of magnetic fields. The sails billow under pressure from the solar "wind" - electrically charged particles from the sun - or from intense man-made plasma beams, which special satellites would aim at the sails.
(Excerpt) Read more at csmonitor.com ...
That's some pretty neat technology!
What will they use for brakes?
I don't know...
Jerry Pournelle describes such technology in his sci-fi novel_The Gripping Hand_.Fans of Pournelle will recognize this technology, which was used by the "moties."
The planet.
I don't want to be first.
it is a FARGATE!
DUH. Forgot about the gravity. That'll stoppem right nicely.
The Moties used a similar technique to the MagBeam concept, but, as I recall, it was a laser cannon.
So, apparantly, for braking, they have to have a plasma cannon at both ends of the trip.
"The team's initial concept involved using the system passively, just as a mylar solar sail would be used. But in developing the lab equipment to test the concept, the team recognized that the plasma "wind" could be provided artificially, through satellites that generate plasma beams. Dubbed MagBeam, the approach would be particularly well suited to traveling to and from other planets, they say. The satellites providing the beams could themselves draw energy from the sun, if close enough, or from small nuclear sources if they were placed in orbit around the outer planets."
"The satellite would aim its beam at the spacecraft, which orbits nearby. As it travels, the beam generates its own magnetic field. As the beam nears the craft, its magnetic field couples with the field the craft itself generates, ensuring that the beam will remain "locked" on the craft for as long as necessary to build the needed velocity. The process could be reversed for braking."
"The satellite would aim its beam at the spacecraft, which orbits nearby. As it travels, the beam generates its own magnetic field. As the beam nears the craft, its magnetic field couples with the field the craft itself generates, ensuring that the beam will remain "locked" on the craft for as long as necessary to build the needed velocity. The process could be reversed for braking."
Wow! 40 days to Mars. That's do-able!
I can understand using this to speed getting from Earth to Mars, but how will it be used in getting from Mars back to Earth?
Good evening.
I'll go first.
Michael Frazier
I'll stand in line after it has been successful about 1500 times. Plus I'll keep my eyes closed. I don't do well with heights.
BTTT
3 - "That's some pretty neat technology!"
"Roasted nuts', anyone?
As for "brakes", any solar sail can accelerate, decelerate, or anything in between.
It is even possible to "tack" and move toward the Sun. The method is left to the reader as an exercise.
I can understand tacking towards the earth using the sun for propulsion. However, I cannot understand tacking towards the earth with a beam of power focused from the earth. I am not aware of boats having the ability to sail directly into the wind. An angle between the boat and the wind is needed.
The whole purpose of this article was to expouse the speed increase available when you focus a beam from the earth onto the sail. That means to me that the trip back would be just as long as ever.
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