A blueprint for clearing the skies of space debris | Hacker News Reader

A blueprint for clearing the skies of space debris

sciencedaily.com

17 pointsmineshaftgap6 comments

Bit on how what the laser does:

> The intense laser beam focused on the debris will produce high-velocity plasma ablation, and the reaction force will reduce its orbital velocity, leading to its reentry into Earth's atmosphere.

So its job isn't to incinerate, which is where my mine initially went :P, just to get objects to fall to earth and get incinerated by the atmosphere.

I wonder how feasible the reverse would be (i.e. using laser-initiated plasma ablation to keep something in space, like satellites or space stations)? Would it be possible to use some sort of heat shield as an "engine", point a laser at it, and send the whole craft to a new orbit?

Sure, but it would seem to just push the same problems elsewhere. For example, it isn't really practical for a flight to Mars because you still need to figure out how to get the laser and its accompanying huge battery to Mars before you arrive in order to decelerate your vehicle. That is probably why the first real implementation would be deorbiting debris. That is a simpler operation that doesn't involve numerous course corrections as it is mostly accelerating objects in one constant relative direction. If everything goes successfully there, they might move on to geosynchronous satellites and so on up the scale of complexity.

I was more talking about orbital maintenance (i.e. counteracting orbital decay) than interplanetary flight, though that now brings up the question of whether such a laser-propelled craft could "bootstrap" itself by having its own laser pointed at its own ablation-plate-thingamajig to propel itself about.

Will this be the first spacecraft mounted laser weapon?

> "we plan to install a full-scale version on the ISS, incorporating a three-meter telescope and a laser with 10,000 fibers, giving it the ability to deorbit debris with a range of approximately 100 kilometers".

Not the first to be _launched_, but perhaps the first to be _orbited_: http://en.wikipedia.org/wiki/Polyus_%28spacecraft%29

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