A meteor broke apart over rural Russia on Friday morning, injuring at least 1,200 people. Hours later, an asteroid known as 2012 DA14 passed about 17,000 miles above Earth’s surface — a close shave in astronomical terms, passing nearer than many of our communications satellites. One was predicted; the other was not.
These events were unrelated, but they underscore how crucial it is that nations know, quickly, what is falling from the sky and what, if any, dangers are posed.
Every day about 40 tons of space debris hit the atmosphere, burn and settle to Earth, NASA has found. The vast majority of the detritus consists of meteoroids no larger than a grain of sand, but even tiny specks pack a wallop: A typical meteor hits Earth traveling at least seven miles per second, at least 30 times faster than a bullet shot from a handgun.… Seguir leyendo »