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New Space Propulsion System Uses Sun's Magnetic Field
0b1 writes "ABC Science News has an interesting article on a new space propulsion system, that may beat voyager to the edge of the solar system." Fascinating. Seems like a lot less hassle than a light sail. For a little more info about this and other proposed "no propellant" space propulsion systems, check this NASA page. Lots of interesting concepts, all unfortunately still at the "dream" stage of development.
Oops, Voyager is not being abandoned, actually Pioneer 10 being abandoned. It might have passed out of the heliopause in May, but further readings should be taken. They won't be.
Having said that, a Microsoft spokesperson is apparently going to announce that ActiveField will be integrated into Windows 2000.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
If a field can be generated which is not a sphere, the distortion may generage some sideways motion. But then the sail would have to be turned off for a while to allow the Sun's gravity to slow the ship's away motion, thus leaving the sideways motion.
If an off-center sail can be created which has no more outward force than the Sun's gravity, the resulting sideways force would dominate. But it won't provide as much acceleration as running with the wind with all sheets out.
If there was any way to tack, then you might be able to exploit the interstellar wind to get just a little bit more acceleration.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
cthulahoops wrote: That's what I'm thinking. If they can get to .05 c then they can get a probe to alpha-centauri in not too much over twenty years + 4 odd years return time for some pretty data. Close up readings of another Star in our life time == good thing.
... or maybe 3 tenths of one percent of lightspeed. The fastest this technique could get a probe to Alpha Centauri would be, oh, 1600 years. Realistically, we need at least an order of magnitude improvement to get it down to a century or so, when it might be worthwhile trying, assuming we can develop long-lived space probes.
Unfortunately, the top speed achieved here is more like 0.0025 c
This is easy to work out -- light speed is ~300,000kM/s and the solar wind is ~1000kM/s. As you can see it's a long way off.
We'd still need a plasma drive of some sort to provide continuous acceleration -- this collector is a start in that direction but it's not yet there.
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{Network engineer in Chicago--looking for work!}
And I won't mention setting off a fusion explosion nearby so your sail can get a kick from that...
Microsoft is expected to introduce ActiveField. :)
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Save the whales. Feed the hungry. Free the mallocs.
There's Bob Forward's ideas on light sails. He proposed (and has written a couple of so-so novels about) a multi-stage light sail.
Essentially, you'd need a number of very powerful lasers and the solar system's biggest Fresnel lens, both of which would remain in the system and provide power to the craft. The light pressure pushes the sail at a reasonable speed to wherever.
Eventually when you need to switch from accelleration to decelleration (so as to remain in the destination system), the main body of the sail detaches from the payload (which retains a smaller sail, pointing in the opposite direction). The main sail then deforms just enough to focus a lot of light at the small sail. This slows down the ship for an insertion orbit into the system.
It's interesting, but would require a hell of a lot of engineering work to build. On the plus side that laser would probably keep alien invasions at bay.
-- This and all my posts are in the public domain. I am a lawyer. I am not your lawyer, and this is not legal advice.
(Mind you, there wouldn't seem much point to it, given that a craft carrying the parts could equally carry instruments and do the work itself. On the other hand, getting Pioneers 10 and 11 in fully-working order would be neat, and worth it for the coolness quotient.)
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
There was tonnes of stuff about it in Scientific American, and then... ...nothing. Silence. It was somewhere between the surreal, a conspiracy theorist's wildest dream, and a monumental botch-up by someone.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
It can be VERY useful. Suppose you want to send a probe to Saturn. Launch it normally, use M2P2 to propell it to Saturn at a low cost. Braking can be done using the same aerobraking manouver used for the Mars mapping probe (whose name escapes me at the moment). Now, it is moving as slowly as they want it to be (within orbital mechanics of course).
hey, there are some really smart people at NASA. i'm sure they've thought of that possibility, and are making batteries in case that becomes a problem. perhaps they'll bring the energizer bunny along with them. or, even better yet, maybe they're setting up the mylar blanket as a dual energy converter, absorbing the light reflecting off of the moon to give power at night. then again, they might just decide that when the sun goes down and they're halfway past jupiter that they need to pull over to the side of the road and take a nap. whatever the fix they come up with for this monumental problem, i'm sure they'll thank you for bringing to their attention the fact that they didn't think this through first, unlike the degree of thinking through that went into your enlightening post. perhaps you should walk into NASA and demand a research and development job. i'm sure they've got positions open for such monumental thinkers as you...
Here is a slightly more in-depth article.
With a big bowl of corn chips. :P
Save the whales. Feed the hungry. Free the mallocs.
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I'm sure people with the proper tools, such as the Satellite Tool Kit orbit calculator or Orbital Mechanics CDROM, can make some interesting launches by using the Earth and Moon to redirect trajectories.
Mars Direct, only moreso. Using this, you could cut down on fuel mass and bring along (a lot) more supplies (and thus make life easier for our mars explorers -- imagine having frozen strawberries once a month instead of Tang).
In any event: this would make getting to the outer planets a lot easier. Instead of having to do a Voyager and visit each one, we could orbit an observer satelite around anything we find interesting out there well within a decade -- all the planets, Titan, Io, Europa; watch 'em all at the same time, 24/7.
Now *that's* a killer webcam site.
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Every year during my review, I just pray the words "slashdot.org" aren't mentioned.
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Every year during my review, I just pray the words "slashdot.org" aren't mentioned.
I can't find the recent news item that Voyager has been sent its last commands. It has a few instruments still operating, but its antenna will drift away from the Earth in September unless new commands are sent. It has to be kept operating until its instruments report it has left the Sun's influence or the size won't be known (I don't remember whether solar magnetism or solar wind is still being measured). I think funding is the problem.
Click on the "related press release" link at the bottom of the page. A big communications satellite ended up in an unusable orbit. Hughes engineers managed to get it to a good orbit by sending it around the Moon. A Google search finds several reports.