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Space Sails Could Bring Used Rockets Back To Earth
GordonCopestake writes "An article from New Scientist proposes that all new spacecraft have sails attached to bring them back to earth — a measure that would reduce the amount of garbage in space. From the article: 'The risk to spacecraft from a collision with space debris could be reduced by equipping launchers with a gossamer-thin "sail." The idea is to deploy the sail after the rocket has released its payload to amplify the drag of the last vestiges of the atmosphere, and so force the rocket out of orbit.'"
Wired has a related story about the risks faced by the space shuttles as they share orbits with tons of drifting space debris. "... in the 54 missions from STS-50 through STS-114, space junk and meteoroids hit shuttle windows 1,634 times necessitating 92 window replacements. In addition, the shuttle's radiator was hit 317 times, actually causing holes in the radiator's facesheet 53 times."
Well, with the kind of weapons tech being developed (electric eye with lasers?), it shouldn't be a big deal burning down these debris. The problem would be allowing (or acknowledging that *anyone* has) that kinda weaponry up there.
Real men read Slashdot articles at -1, bottom up.
The debris in low orbits where the Shuttle operates will return within just a few years. Higher than that means it stays up longer.
If an object is orbiting twice as high as the shuttle, about 500 miles, it'll stay up roughly a couple centuries. Just a bit higher than that and you're measuring orbital lifetimes in millennia.
Fascism trolls keeping me up every night. When I starts a preachin', he HITS ME WITH HIS REICH!
The 317 hits were over 54 missions. ~6 hits per mission.
Space is not earth.
Moving things in space and keeping them from crashing into the atmosphere requires energy. Energy means fuel and fuel means you need to pay to send it up. Docking objects in space requires complex electronics which means even more mass to send up.
Recycling requires a highly advanced and complex industrial base which doesn't exist in space. If it did then you wouldn't need the junk since you can mine your own raw materials.
Densities of materials vary widely, but as a rule of thumb, mass increases with the cube of an object's size, but drag only increases with the square.