Space Sling

Planetary Slingshot
Traveling to the planets is an expensive business. It takes powerful booster rockets to lift a craft into space, then give it enough "kick" to reach another world. But engineers are working on ways to propel spacecraft for a lot less money -- including an orbiting "slingshot."

The idea behind the slingshot is to use the Sun and Earth's magnetic field to fling a spacecraft from a low Earth orbit to a high orbit or beyond.

The system would use a long, skinny cable. The electrically conducting cable would spin end over end, like a stick thrown to your pet dog. It would catch a spacecraft at one end, then release it as it spins around. This would speed up the craft by a good amount.

After that, the cable would convert solar energy to electricity and feed it along the entire cable. Earth's magnetic field would push at the charged cable, boosting it back to a higher orbit for the next maneuver.

The cable could also catch a spacecraft returning to Earth after a mission to another body -- perhaps carrying samples of Mars or a comet.

The system is still in the developmental stages, but engineers have tested a similar system during shuttle missions. If the slingshot works, it could reduce the need for the upper stages that propel craft out of orbit on their way to the planets. That would cut costs by quite a bit, making it possible to fly more missions for the same amount of money.



Script by Damond Benningfield, Copyright 2004

I heard this on my raido station today. Stardate is a daily astronomy breif and this one seemed intresting whats everyones take? sounds cool to me.


stardate.org...

[edit on 11-2-2005 by Mizar]

It sounds like quite a neat idea. Possibly even as a rival for a space elevator.

The website seems quite nifty too. I'm going to add it to the Forum Library (as soon as I get my capability to edit my posts back, that is.)

I heard the same story today. Here in vegas, Stardate is played kinda inbetween things on NPR. Brian Green, author of "The Elegant Universe" was on Fresh Air today. Its was a good one!

Physicist Brian Greene on 'The Elegant Universe'


Fresh Air from WHYY, February 11, 2005 · With his book The Elegant Universe he developed a reputation for explaining complex scientific theories with insight and clarity. The book was the basis of a PBS series. His new book is, The Fabric of the Cosmos: Space, Time, and the Texture of Reality. Greene is a professor of physics and mathematics at Columbia University. He received his undergraduate degree from Harvard and his doctorate from Oxford, where he was a Rhodes scholar. This interview was originally broadcast on March 16, 2004.

well sounds intresting,cost is probably one of the biggest issues in flying craft into space so if it saves money and build time and costs are attractive its got to be worthy?

Yeah I missed that on fresh Air. I wanted to listen to it. the NPR raidio strations are the best. no comericals and great shows.

I'm sure that the methods of flying as used by gliders ( as well as motorised or engined aircraft also ), could be coupled with knowledge of the Earth's rate of spin, and direction of spin, to make it yet easier again to get the escape velocity just right with minimal power input.

Here is an example of delivery to the tether:

work.offshore.ai...

Instead of some airplane/reusable rocket combo to carry payload to the tether, I was thinking of a second sling in the atmosphere, a stratospheric balloon in the shape of a wheel at 30-40 km wich pick up a cargo with a suspended tether from the ground and using centrifugal accelleration, hurl it some 30-40 km above the balloon, where it can be handed over to the tip of a spacetether.

The balloon is connected to the ground with a second tetherloop, that will spin the baloon using a ground based elictrical generator, this will seperate the heavy energysource from the vehicle, and it means the electric propulsion could be provided by wind or solar energy, wouldn't it be nice if we can get things into orbit without spraying buckets of hydrazine??


Considering the sheer length of the tethers suspended from the balloon and the counterweight to balance the slingaction, I would think we talk about a blimp 1 or 2 times Hindenburg size, but I think its could be done with over the counter materials, just add money... well, a lot of money


[edit on 12-2-2005 by Countermeasures]

There's an old pilot's joke about slings, but this is a family site. Sigh.

Mr. Space Tether, Dr. Robert Forward died a while back, so in the best tradition of dead artists now everybody is talking about his work. His company still exists and can be viewed here.

Who was Jack, and what did he know about beanstalks when?