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22 replies to this topic

### #21 d3k3

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Posted 13 November 2010 - 03:36 PM

Even if the pure slingshot without using the engines is debatable in this scenario you could definitely use the Oberth effect to dramatically reduce the amount of fuel needed to launch rockets into space. The rocket could accelerate from the surface toward the center of the earth without burning any fuel at all and then fire its engines when it reached the center. It could then achieve the escape velocity using a lot less fuel than would require in a conventional launch.

It is not debatable. You need to be in a different orbit than the body you get the slingshot from. Period.

You make a good point about the Oberth effect, but I'm not sure how it would work in this situation. One problem is that the math no longer behaves when you're "orbiting" inside the body. For starters, you no longer have a constant gravitational parameter (effectively mu = 0 at r = 0), so you can forget about using vis viva.
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### #22 ItsGneiss

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Posted 13 November 2010 - 09:29 PM

Well, it seems to me that one can only fall halfway through the Earth, because then you're falling "out" (or "up"). "Up", "Down" and other directionality is relative in space.
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### #23 Akriti

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Posted 14 November 2010 - 06:57 AM

Spoiler for

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Value of a Woman :
She came out a man's ribs. Not from his feet, to be walked on, nor from his head, to be superior over, but from his side to be equal..........
Under the arm to be 'protected', and next to the heart to be 'loved'. <3

Brushes flowing free
Tender strokes of careful love
Painting one's true heart -- Framm

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