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To: HamiltonJay

You could use gravitaion from variois bodies to slow down, but it would be complicated.


21 posted on 10/19/2009 8:23:55 AM PDT by Republican Extremist
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To: Republican Extremist

In Forward’s “Saturn Rukh” they used cables made of carbon fiber nanotubes fired into the moons to asist climbing into and out of Saturn’s gravity well.

Forward was a physisist so his science fiction got pretty technical and was well beyond my understanding with a lot of it.


25 posted on 10/19/2009 8:43:14 AM PDT by cripplecreek (Seniors, the new shovel ready project under socialized medicine.)
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To: Republican Extremist

Yes, but can you predict where those bodies are going to be?

You have an inbound traveling and near light speed, in interstellar space, its coming up on a solar system, with your goal of landing on the 3rd planet from that star, you have say 6 planets outside your goal, in various places of orbit around that star..etc etc etc. And perhaps even other bodies you don’t know about because your observations of the system are from light years away.

I am not saying the math couldn’t be done to figure out a way of doing it, but remember, this all has to happen automatically.

The fastest spaceship we’ve had to navigate to date hit a top speed of 3.3AU per year, or approx 500,000,000 KM per year, and that was around a solar system we know pretty well. Light speed is 220,000 KM PER SECOND!...

To give you an ideaof the speed differencials here, our fastest spacecraft to date that we have dealt with is moving at little more than 15KM/second.. a craft traveling at the speed of light is traveling at 14667 times that speed. And it took us slingshotting that craft around several gas giants to accomplish that great speed of 15KPS. To slow a craft from light speed to an orbital velocity of say an earth like planet 27 KPH or .0075 KM per Second.

So, we need to bleed off 220,000 KPS to .0075 KPS just to achieve orbit around an earth like planet if we are travelling near the speed of light. Now, could we get there by repeated flybys of palnets using gravitational wells to slow down etc, certainly.. but you’ll been orbiting that destination sun a LONG LONG time, assuming you don’t collide into anything unexpected in the process to bleed off all that speed.

I am not saying it isn’t theorhetically possible, I’m saying its a very very difficult problem. When you have knowns like our own solar system, its difficult enough, to say, go do this all on your own without help.. its a wholey different story.

Lets just conjecture that we have a HUGE gas giant we can use the gravity of in our destination to slow down, and lets say we can bleed off 10KPS every time we pass it, and lets say we can pass it an average of once a year, that’s still a 22 year slow down wait once the vehicle gets there.


27 posted on 10/19/2009 8:54:40 AM PDT by HamiltonJay
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