Posted on 10/28/2004 8:49:44 AM PDT by vannrox
Oct. 20, 2004 — A team of University of Washington researchers believes it has found a way to cut roundtrip travel time between Earth and Mars by 95 percent, giving astronauts a much higher chance of pulling off a successful mission while minimizing their exposure to dangerous radiation.
"If it's going to take 2 1/2 years (to travel back and forth to Mars), the chances of a successful mission are pretty low," said project head Robert Winglee, a professor of Earth and space sciences at the Seattle-based university.
Taking a cue from the sun, Winglee has come up with a plan to beam magnetic particles, much like how solar wind particles stream from the sun, onto a spacecraft equipped with a magnetic sail. The craft would be pushed along as the particles repel from the sail.
Winglee envisions setting up beam generator on a space station that would send streams of magnetized ions toward the spacecraft's sail. The vehicle's speed would increase with the size of the plasma beam. For example, a beam generated by a 32-meter (105-foot) diameter nozzle would blast a spacecraft more than 26,000 mph or 625,000 miles per day.
Mars and Earth average about 48 million miles apart, though the distance at any one time can vary greatly, depending on where the planets are in their respective orbits around the sun. Winglee figures a spacecraft traveling on magnetic beams would take about 76 days for a one-way journey, but he's working on plans to shave even more time off the voyage.
Quicker travel times, however, would require a plasma station near the destination point to generate a force for braking.
The technology, called magnetized-beam plasma propulsion, or mag-beam, was among the projects under discussion this week at NASA's Institute of Advanced Concepts symposium in Seattle. The space agency this month gave Winglee's team a $75,000, six-month study contract, with the possibility of a two-year, $400,000 extension.
Winglee touts mag-beam technology as a way to open the solar system for exploration. With plasma generators placed around the solar system, spacecraft could sail from point to point, quickly and cleanly. A test mission could be ready to fly within five years, depending on funding.
"This would facilitate a permanent human presence in space," Winglee said. "That's what we are trying to get to."
Much work remains before mag-beam technology becomes practical, said Louis Friedman, executive director of the Pasadena, Calif.-based Planterary Society, which is preparing to launch a solar sail craft early next year.
The spacecraft taps the steady flow of solar wind particles beating against its sail to move.
"We didn't look at mag-beam for our mission. It's interesting, but it's an idea that is not very mature," said Friedman.
They should take the sort cut through the sun.
This is a stretch..
I'm not sure how the human body could handle that accerleration.
I can't help but wonder what would happen to the space station emitting this plasma beam: where would it end up after driving the spacecraft toward Mars?
Remember Sir Isaac's First Law...
There is, however, the minor difficulty of coming back the same way....
Is there any science that says this is possible? Has there been any measurable push from any beam to date?
Actually, the acceleration would be quite gentle - it would just be constant which would result in much higher speeds than rocket technology can achieve.
do you mean 26,000mph?
TLI burn for Apollo accelerated craft to 406miles/min or about 24,360mph (roughly)
what sweet dreams of mars??? I mean for God sake we havent saved those poor souls on gilligans Island yet.
This guy's read the 'Mote in God's Eye' (although that was a laser beam).
but at 48million miles average, what is the actual length of the trajectory over travel time? (assuming optimum launch).
If the trajectory was truly 48million miles, then 600,000 miles per day wouldn't be that hard to achieve I think. Probably need to pre-position fuel or boosters in space.
because if something goes wrong, you'll need a lot of fuel to get back.
As long as there is a constant accelleration of 1G, they could get there much faster than 90 days. So the human body could easily survive the trip. However, the beam technology is suspect. The 'station' would not be able to maintain a stationary position if it's indeed sending a stream of plasma to the ship. That's simply not going to work. NASA is already working on plasma propulsion (I have a good friend working on plasma propulsion) which will be the way to explore our system. There is more than enough propulsion energy to get us around the solar system using plasma engines (like the impulse engines in Star Trek). Problem is, you need nuclear generators on the ship (like our subs have). Some people don't like nuke power in space. We *will* explore our system with manned missions, it is simply too important not too. I believe no matter who is president this will be true, but let's face it, we need to be fiscally responsible about our current spending. This is why I am very much in favor of privatization of space exploration (though we need military organization as well).
OK, not really a techno geek, but if they are shooting magnetized particles at a sail, presumably it is attached to a ship with computers on board. Don't magnets and computer drives not play well together? Just a thought.
I'm not sure how the human body could handle that accerleration.
The acceleration is probably a few tenths of a G. A plain solar sail is about .01G.
What gives you the speed is the amount of time you apply that 0.2G. For a few minutes, you exceed the highway speed limit. For a few days, you get up into the tens of thousands of MPH.
Also try Pournelle's Solar Sail Project. Short stories mixed with technical essays.
It may seem impractical now, but on the gripping hand, it is Crazy Eddie enough to work.
I'm surprised you have Internet access on Gilligan's island - how's the weather there?
Sounds like it would be a breeze!
Remember that robot that walked to the island? he had Wi-Fi, a laptop and a cell phone with him.
of course, we have to recharge the batteries on the cell phone by stirring coconuts to create current.
Tonight, we're having fish and coconut cream pie for dinner. Ginger will do an acting scene, Mary Ann will drone on about Kansas, the Howell's will brag about their money, the Professor will invent something, and the Skipper will likely whack Gilligan with his hat for goofing up the rescue event.
IOW, business as usual.
I recognize Kerry in the Center, and Breck Girl on the left, but who's that on the right, mostly turned away ???? (evil grin)
I don't get it. How does aiming a powerful beam of radiation at the spaceship minimize the exposure of the astronauts to radiation?
Two years? We can do better than that with chemical rockets. Did you mean 2 months?
I'll be the spoilsport who suggests that with our modern computing power, we needn't send people to Mars.
We could do 100 sample recovery missions (accepting a portion that failed) for the cost of a single manned mission that achieved far less. Or ten unmanned missions for one tenth the cost of a single manned mission.
Hah! (BTW, didn't think much of the second book).
Can't resist asking where are you going to sleep tonight?
LOL, well, I'm thinking about putting up a hammock!
Remember the episode where the spacecraft landed and the scientists thought it was on Mars? then the pot of glue exploded and they all ran through the feathers. The scientists thought there were chicken people on Mars and the big one was trying to make the skinny one lay an egg.
TV was better back then. Sillier, but better.
THANK YOU! A spacecraft with a solar sail does NOT work like a sailboat at sea. A solar sail equipped spacecraft can go in one direction - away from the sun. It can be redirected only slightly, but will always be moving outbound. You cannot tack into the solar wind and come back towards the sun, because you do not have the resistance of the ocean against the hull like in a sailboat. No rudder, no keelboard, and you are not displacing anything. A solar sail equipped ship goes out, and does not come back.
I just realized something -- if the generator can send that many ions toward a spacecraft, it's going to get one hell of a push in the opposite direction. Conservation of momentum, and all that.
Wonder how they intend to counter it?
ping
I don't think that's realistic.
They should used the gravity drive the aliens used in the spaceships studied by Bob Lazar
Robots can't notice something unusual in the shadows and walk over for a closer look, just yet.
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