I'm sure you've all seen this shot of the space junk orbiting our blue marble at some point in the last few weeks. It's been practically inevitable since the somewhat-less-inevitable collision between Iridium and some floating Russian nuke-a-lite.
My immediate reaction to this photo was a good deal of annoyance—yes, it does properly highlight all the floating space debris, but it does it in a way that's a little misleading. Specifically, these satellites are all represented as being monstrously huge. In fact, if you look at the photo at right, you'll see that one of these pieces of space trash is supposedly half the size of Sri Lanka. Now, Sri Lanka is over 100km across and is at least ten times bigger than the biggest meteorites ever recorded to strike the Earth. You know, like the one that killed the dinosaurs.
So, let's put this into perspective. There are 12,000 catalogued items of space refuse out there, just under half of which are blocked by the Earth itself. That leaves us with 6,000 or so, and I estimate that there are about the same number of, say, 1949 Volkswagen Beetles out there (assuming about 10% of the 1949 models have survived). DeLoreans still on the road1. It's pretty reasonable to think that many of these objects will be about the size of a VW, too. So imagine, if you will, this same photo but instead of these few thousands icons, you're really seeing the few thousand 1949 VW Beetles DeLoreans on the surface of the Earth. What do you think that would look like?
1 Maybe DeLoreans are better examples. When was the last time you saw a DeLorean?
I saw a DeLorean last year late august, and again not too long ago. couldnt even say how long its been since i saw a split window bug.
I think the '49 was a better example. even though the DeLorean looks more like a satellite.
True. Now that I think about it, exotic or vintage cars are probably crappy examples because they're often kept in garages.
No matter. 12,000 anythings that are the size of satellites scattered across the globe are going to be pretty scarce. And if they're on the surface, that's even one fewer dimension than out in orbit.
--D