You're lucky to be alive.
You weren't flattened by the remains of a seven-ton NASA space derelict entering Earth's atmosphere sometime somewhere at 17,000 miles per hour.
The 12,500-pound Upper Atmosphere Research Satellite, launched in 1991 and decommissioned in 2005, has a 3,200-to-one chance of striking one of us in a 500-mile debris path.
Not bad, since an intact spacecraft or launch-vehicle orbital stage falls back to Earth on a weekly basis.
Most burn up completely on reentry, depending on composition and other factors. Big ones such as the UARS, however, have a greater number of survivable parts.
Oh joy.
NASA's International Space Station, the largest man-made object orbiting Earth, avoids becoming space junk by periodically remaneuvering.
Meanwhile, let's hope UARS hits some barren, useless wasteland. Like Texas. (25 SEPTEMBER 2011)