So the cogent question is, why did humans not detect this morning meteor the size of a bus before it exploded over
Chelyabinsk [link to photos]with the force equivalent to 30 Hiroshima bombs? The shock waves blew out windows and rattled buildings injuring 1100. NASA is actively scanning the heavens for objects in near Earth orbits, but the short answer is, the object was too small to register on any of our near-Earth surveys. Congress mandated in 1998 that NASA identify potentially hazardous objects a full 1km in diameter, or big enough to alter the course of civilization. That threshold was lowered in 2005 to 140 meters in diameter, or regionally devastating. This meteoroid's trajectory took it behind the moon and approached Earth from the direction of the Sun making it difficult to detect, if instruments were watching for it. Europe's near-Earth survey said current information indicates the
meteor was a small asteroid one-third the size and traveling in an opposite direction from asteroid DA14 which passed 17,000 miles above Earth as expected. A survey scientist also
said, "there is no way the meteor could have been detected with the technical means available today." Even a smaller object traveling 65,000kms/h can be catastrophic if a city suffers a direct hit because F=Ma. Chelyabinsk is a city of 1 million and home to nuclear facilities. The meteor broke up in the atmosphere about 30-35kms high, but some fragments or meteorites struck the ground, one making a 20 foot hole in the ice of a nearby lake.
[photo, right] It is a stroke of good fortune that Russia's military did not mistake the meteor for an incoming ballistic missile.
meteor was a small asteroid one-third the size and traveling in an opposite direction from asteroid DA14 which passed 17,000 miles above Earth as expected. A survey scientist also said, "there is no way the meteor could have been detected with the technical means available today." Even a smaller object traveling 65,000kms/h can be catastrophic if a city suffers a direct hit because F=Ma. Chelyabinsk is a city of 1 million and home to nuclear facilities. The meteor broke up in the atmosphere about 30-35kms high, but some fragments or meteorites struck the ground, one making a 20 foot hole in the ice of a nearby lake.[photo, right] It is a stroke of good fortune that Russia's military did not mistake the meteor for an incoming ballistic missile.