Last week, a huge meteorite weighing about 7,000 tons slammed into the Ural Mountain region of Russia, injuring more than 1,000 people.
Every day, millions of meteoroids — bits of space debris, usually left behind by comets or asteroids — enter the Earth’s atmosphere. Sometimes the Earth’s orbit crosses a large number of meteoroids at the same time, resulting in a meteor shower.
These bits of debris, which are made up of rock and various minerals, range in size from a grain of sand to massive boulders as large as 33 feet across. Anything larger than that is deemed an asteroid.
Most of these meteoroids burn up in our atmosphere and disintegrate, but some make it to the ground. A meteoroid that survives its passage through the Earth’s atmosphere and collision with the Earth’s surface is called a meteorite.
While the object that struck Russia was actually much larger, it didn’t survive its impact with the Earth in tact, but fragmented into several much smaller pieces.
Meteorites look very different from terrestrial rocks, mainly because their trip through the Earth’s atmosphere heats them to super-high temperatures, causing them to melt. Many have interesting textures, including depressions or so-called “thumb-prints,” on their surfaces from the ordeal.
Overall, the odds of any specific individual being struck by a meteorite are very slim — about one in 21 trillion. Your odds of winning the lottery are much higher. While many injuries were reported as a result of last week’s impact, all were the result of broken glass and other objects sent flying when the big space rock touched down.