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[PS] Liquid Water on Mars! Really for Real This Time (Probably)
Jeff Findley wrote:
You're right. I got the two mixed up. Kuiper belt is closer in and according to Wikipedia it should contain an estimated "100,000 KBOs over 100 km (62 mi) in diameter". You start with some small ones (easier to move in a "reasonable" timescale) then work your way up in size as the reliability and size goes up on the tugs. I would think you would look for objects that are about to have a close encounter and nudge them so one drops in and one is flung out. -- Mvh./Regards, Niels Jørgen Kruse, Vanløse, Denmark |
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[PS] Liquid Water on Mars! Really for Real This Time (Probably)
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[PS] Liquid Water on Mars! Really for Real This Time (Probably)
Le Aug/8/2018 Ã* 11:54 AM, Jeff Findley a écritÂ*:
In article , says... Jeff Findley wrote: You're right. I got the two mixed up. Kuiper belt is closer in and according to Wikipedia it should contain an estimated "100,000 KBOs over 100 km (62 mi) in diameter". You start with some small ones (easier to move in a "reasonable" timescale) then work your way up in size as the reliability and size goes up on the tugs. I would think you would look for objects that are about to have a close encounter and nudge them so one drops in and one is flung out. Well, yes, the actual implementation might be far more complex than "nuclear tugs to move Kuiper belt objects". One possible argument against flinging one object in while flinging another out would be loss of potentially useful mass from the solar system. The mass we have is the mass we have to work with. Making everything as mass efficient as possible would be the goal. Of course, you'd have to run the numbers on all this. It could very well be that flinging one mass out saves so much mass on the one directed inward that it's worth the cost. But with highly efficient nuclear engines, I kind of doubt that. It doesn't have to be one object flung out and the other drops in. Many scenarios are possible. I think the most likely scenario would be one object is flung into a slightly more energetic (meaning kind of higher) orbit, the other one goes near Neptune and from there to Mars. Even the one going to a more energetic orbit, might be in an orbit that makes it easier to go to Mars. That orbit might be more eccentric. It is easier to bring down an object in an eccentric orbit than a circular one. Well that last sentence is an over simplification, but I think it gives the right idea. Even without using a planet, it doesn't have to be one flung out the other drops in. If one object gets into a more energetic orbit the other must go into a less energetic orbit because of conversation of energy. But the more energetic orbit doesn't have to bring the object further away from the sun. The one with the more energetic orbit could be on a hyperbolic path that crosses Mars. It would therefore slam into Mars quite hard, but I don't that would be very important. Once you accept having objects from the Kuiper belt slamming into Mars, a few more km/s wont do much difference. Alain Fournier |
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[PS] Liquid Water on Mars! Really for Real This Time (Probably)
On Aug/8/2018 at 8:59 PM, Alain Fournier wrote :
Le Aug/8/2018 Ã* 11:54 AM, Jeff Findley a écritÂ*: In article , says... Jeff Findley wrote: You're right.Â* I got the two mixed up.Â* Kuiper belt is closer in and according to Wikipedia it should contain an estimated "100,000 KBOs over 100 km (62 mi) in diameter".Â* You start with some small ones (easier to move in a "reasonable" timescale) then work your way up in size as the reliability and size goes up on the tugs. I would think you would look for objects that are about to have a close encounter and nudge them so one drops in and one is flung out. Well, yes, the actual implementation might be far more complex than "nuclear tugs to move Kuiper belt objects". One possible argument against flinging one object in while flinging another out would be loss of potentially useful mass from the solar system.Â* The mass we have is the mass we have to work with.Â* Making everything as mass efficient as possible would be the goal.Â* Of course, you'd have to run the numbers on all this.Â* It could very well be that flinging one mass out saves so much mass on the one directed inward that it's worth the cost.Â* But with highly efficient nuclear engines, I kind of doubt that. It doesn't have to be one object flung out and the other drops in. Many scenarios are possible. I think the most likely scenario would be one object is flung into a slightly more energetic (meaning kind of higher) orbit, the other one goes near Neptune and from there to Mars. Even the one going to a more energetic orbit, might be in an orbit that makes it easier to go to Mars. That orbit might be more eccentric. It is easier to bring down an object in an eccentric orbit than a circular one. Well that last sentence is an over simplification, but I think it gives the right idea. Even without using a planet, it doesn't have to be one flung out the other drops in. If one object gets into a more energetic orbit the other must go into a less energetic orbit because of conversation of energy. But the more energetic orbit doesn't have to bring the object further away from the sun. The one with the more energetic orbit could be on a hyperbolic path that crosses Mars. It would therefore slam into Mars quite hard, but I don't that would be very important. Once you accept having objects from the Kuiper belt slamming into Mars, a few more km/s wont do much difference. Oups! That was nonsense. Except for Pluto and a few others of similar sized Kuiper belt objects passing close to another Kuiper belt object will only make a very small trajectory change. It isn't worth the trouble to get a gravity assist from another Kuiper belt object (except if it is with one with a mass close to Pluto). So I would think that to move Kuiper belt objects to Mars, you would find one that is going close to Neptune, nudge its trajectory so Neptune sends it towards Mars, possibly with a detour by some other planet. Alain Fournier |
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[PS] Liquid Water on Mars! Really for Real This Time (Probably)
Jeff Findley wrote on Wed, 8 Aug 2018
11:54:41 EDT: In article , says... Jeff Findley wrote: You're right. I got the two mixed up. Kuiper belt is closer in and according to Wikipedia it should contain an estimated "100,000 KBOs over 100 km (62 mi) in diameter". You start with some small ones (easier to move in a "reasonable" timescale) then work your way up in size as the reliability and size goes up on the tugs. I would think you would look for objects that are about to have a close encounter and nudge them so one drops in and one is flung out. Well, yes, the actual implementation might be far more complex than "nuclear tugs to move Kuiper belt objects". One possible argument against flinging one object in while flinging another out would be loss of potentially useful mass from the solar system. The mass we have is the mass we have to work with. Making everything as mass efficient as possible would be the goal. Of course, you'd have to run the numbers on all this. It could very well be that flinging one mass out saves so much mass on the one directed inward that it's worth the cost. But with highly efficient nuclear engines, I kind of doubt that. Yes. I would expect that 'flinging out another' would always be more efficient if you ran it through a nuclear thermal engine to speed it up in the direction you want to fling it. -- "The reasonable man adapts himself to the world; the unreasonable man persists in trying to adapt the world to himself. Therefore, all progress depends on the unreasonable man." --George Bernard Shaw |
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