Space debris is a green issue that few people ever discuss -- or even think about. There is a ring around our Earth of space junk – more than 9,000 man-made items, total, ranging from nuts and bolts to large, now-defunct communications satellites weighing thousands of pounds. Most of these objects will just orbit peacefully for decades and then begin to fall and disintegrate completely before touchdown. But sometimes when the larger satellites lose power prematurely and descend from their orbits, pieces of them can touchdown in populated areas. Not only is there a slight threat of property damage, there is also a risk of damage to the environment, as some of these satellites contain hazardous materials.
Case in point is today’s
article on CNN News about a U.S. government satellite that it expected to fall sometime this February or March, as a result of it losing power. According to the report, the satellite “could contain hazardous materials, and it is unknown where on the planet it might come down.” Gordon Johndroe, a spokesman for the National Security Council, was quoted as saying: "Appropriate government agencies are monitoring the situation." Sounds kind of like a warning to me.
"Numerous satellites over the years have come out of orbit and fallen harmlessly,” Johndroe said. “We are looking at potential options to mitigate any possible damage this satellite may cause."
Apparently there is some speculation that the government might shoot the satellite down using a guided missile system. According to the article, “NASA engineers successfully directed a safe de-orbit of the 17-ton Compton Gamma Ray Observatory,” in 2000, “using rockets aboard the satellite to bring it down in a remote part of the Pacific Ocean.”
According to the report, the 78-ton abandoned space station Skylab, which fell out of the sky in 1979, was the largest piece of space junk to plummet to Earth to date. It scattered its debris across the Indian Ocean and a remote section of western Australia. Apparently there are no incidences of anyone ever having been struck and killed by falling man-made space debris.
Not only does this space junk pose a slight threat property, and possibly people, on the ground, but it also poses a threat to manned space missions, like the U.S. space shuttle program, and manned space stations, not to mention research rockets. If a space station, or one of the space shuttles, ever collided with one of these objects as it was coming down, the result could be catastrophic.
There is growing awareness about the problem because as we launch more and more communications satellites, the number of big, heavy, and possibly dangerous space junk items is going to grow quickly. I should point out that
the U.S. isn’t the only country responsible, Russia, China, India, Japan and France also all contribute to the problem, so its going to take an international effort to do something about it.
… and then there’s the minor point that no one has really come up with a viable solution to the problem!
