NASA's Top 10 Space Junk Missions

Ant writes "NASA has identified the top ten space junk missions and said over 19,000 pieces of space junk are known to exist..." That's nothing: You should see my living room.

Comments

Questions questions questions

[teebob21]

For the sake of discussion, let's assume this report showed a problem orders of magnitude worse, and we were on the verge of Kessler syndrome conditions. What technologies exist today to combat the problem? (Yes, I know, no government today would unilaterally scrub space without a quid pro quo...)

If there are 19,000 trackable chunks of debris, how many untrackable (and just as deadly) small particles are there? I know that particle densities are minute. If we launched an array of satellites with Aerogel paneling, is it reasonable to expect a significant improvement in "air" quality up there?

What about that heat-ray device recently pulled our of Afghanistan? Can we launch one of those to spray microwaves tangentially to the Earth's surface? Would the heat applied to a paint-chip sized debris particle be enough to change the orbit? It doesn't take too much delta-v to alter the eccentricity of a paint fleck enough to burn up in orbit, does it?

(Less coffee, more sleep next time, methinks)

Short answers, more like guidelines

[starglider29a]

In no order:

• It takes the same delta-v to de-orbit any two masses in the same orbit. Paint chip or Star Destroyer. Thrust requirements follow Newton, not Roddenberry.
• Whatever energy you have to apply to an object must be applied to the object. It's 100km away at 7km per second. Good luck.
• The delta-v to get close enough to where you can apply delta-v (bump a paint chip) adds up. If you could hit it with a beam from 100km away, that would be great, but delivering delta-v at 100km is problematic.
• Almost nothing is magnetic, so forget that. We don't have a tractor beam, and Yarkovsky Effect is insignificant on these tiny pieces. A maser/laser doesn't deliver momentum very well. Heat does nothing.
• Blobs of Aerogel in a counter-directional/retrograde orbit could sweep up the small stuff, but the volume that needs to be swept is like mopping a basketball court with a cotton swab.

Solve the "how do you apply force at a distance" issue and yer halfway there.

Re:Space sized bin bag

[Martin Blank]

Setting up a net isn't that easy. Aside from the 19,000 "large" items (those over about 10cm), there are tens of millions of smaller items like washers and paint flecks. Let's say there are 50 million such objects between altitudes of 150 miles and 300 miles. That space totals up to 11.7 billion cubic miles for an average about 235 cubic miles per piece of debris. There are, of course, higher densities in some spots, but not enough to make something like this economical.

Additionally, aerogel is some fragile stuff. I know it is, because I have some at home. It came from a polite request to purchase some small, random piece from an aerogel manufacturer about ten years ago, and the person who replied was kind enough to simply put a piece of shop scrap in a plastic box and send it to me (complete with MSDS). Within ten minutes of opening it and despite what I thought was careful handling, I had broken the piece in two, and in the intervening years, it has broken further into about six major pieces and a dozen minor bits. It may be good for capturing micrometeors, but it would shatter if it were hit by a bolt, adding to the debris problem.

As for who gets back the space debris and whatever else is deorbited, the answer should be "nobody." Send it to break up over the Pacific. If a country wants something back badly enough, they can design the important parts to survive re-entry and bring it back on their own, or provide funding for a dedicated retrieval mission.