Coming Soon to Earth: Radioactive Space Debris
Last week, a US satellite collided with a Russian satellite. And this accident could be just the beginning.
Since the launch of Sputnik, Americans and the former Soviet Union raced each other to send more and more satellites into space. And most of that hardware is still up there. It’s called space debris, and in the fifty years that man has been exploring the vacuum that envelopes the 
planet, there have been more than 6,000 satellites launched into orbit, half of which are not longer functioning. And now, as more and more nations are joining the Americans, Russians, and the Europeans in placing more potential debris into the low-orbits, the problem of space debris may get a whole lot worse.
There is an estimated 14,000 objects that are larger than 4 inches or 10 centimeters. The US and Russia actively track about 17,000 objects that are floating around in space for fear that these objects may collide or even penetrate something like the International Space Station, the Hubble Telescope and its cousins, or the ever-smaller US Space Shuttle fleet.
Worse yet, some of that junk up there is radioactive.
Currently, 44 radiation sources from Russia are parked in the burial orbit. They are: two satellites with unseparated nuclear power units (Cosmos-1818 and Cosmos-1867), fuel assemblies and 12 closed-down reactors with a liquid metal coolant, 15 nuclear-fuel assemblies, and 15 fuel-free units with a coolant in the secondary cooling loop. They are to spend no less than 300 to 400 passive years in the orbit. That is enough for uranium-235 fission products to decay to safe levels.
The United States is another contributor to the high levels of radiation in near-Earth space. In April 1964, its Transit-SB navigation satellite with a radio isotope generator aboard failed to enter orbit and broke into pieces. While burning up in the atmosphere, it scattered about a kilogram of plutonium-238 over the western part of the Indian Ocean north of Madagascar. The result has been a 15-fold increase in background radiation around the world. A few years later, the Nimbus-B weather satellite with a uranium-235 reactor crashed into the Indian Ocean. Today, there are seven American radiation sources circling the Earth in orbits ranging from 800 kilometers to 1,100 kilometers, and two more in near-geostationary ones. –Ria Novosti
After the US-Russian collision, Russia is being warned by scientists that wreckage could land in Siberia. The Kosmos line of military satellites have been known to carry nuclear reactors on board. So far, the Russians are not confirming if the satellite involved in the collision is indeed radioactive, but they seem to be taking the warnings seriously, especially as Lake Baikal is in the area that wreckage may affect.
satellite, US, Russia, collision, space debris, Sputnik, Siberia, military, radioactive, wreakage, Lake Baikal
March 12th, 2009 at 6:02 pm
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