There are two flavors of space junk. The obvious things are dead satellites, so they've been up there, their mission is over, they've expended their fuel, batteries out, solar rays are dead, so they're sort of dead satellites. But there's also a lot of other debris, which is you have the rocket boosters that launch them into orbit.
People are worried about debris landing on the ground or hurting somebody or property, but in fact, the more significant concern is you have all this space junk flying around and you have the most debris where you have the most satellites. Everybody uses GPS to get from here to there. We have satellite television, we have weather reports, the Landsat data is used for all sorts of purposes with governments assessing their resources, assessing health of forests, farmers use for satellite data for monitoring crops.
If you have a piece of satellite debris, you're whacking into a satellite, in the worst case you now lose that capability and in February of 2009, that actually happened where there was a iridium communications satellite that collided with a dead Russian satellite and so that basically took out a $50 million, 100 million dollar satellite that was working and doing something useful.
The Department of Defense and other government agencies contacted the national laboratories and said you have these wonderful resources, can you help with this concern? We've got the supercomputing people, the models, people doing sensors so you can go through and predict what would the radar see, what would the optical sensor see when we design the satellite system to sort of supplement the current capability and enhance the current capabilities.
There's about 20,000 objects that the JSpOC (the Joint Space Operations Center) is tracking debris for the U.S. government and that information gets shared with companies and other countries if they ever see that there's a potential threat to a satellite, they will notify the owner of that satellite. Currently there's a disconnect in the sense of the things that are easily tracked are about four inches in size and larger. But things as small as a marble, so about a half an inch, are large enough to do serious damage to a satellite. So, there's somewhere between a hundred thousand, 200,000 pieces of debris that we would like to be tracking.
And so the supercomputing capabilities that we have here at Livermore are one way to keep track of that. We take all the information we get and share it with other satellite owners to basically help everybody out.