ST. LOUIS (KMOX) - It was a jolt of a lifetime for thousands of Russians who live about 900 miles east of Moscow.

A meteor slams into a mountain region but nearby, parts of buildings fall, windows break, and people are injured, mainly by flying glass.

Professor of Earth and Planetary Sciences at Washington University, Bill McKinnon says they are asteroids when in outer space, meteors when they enter the atmosphere and the smaller pieces that break off are meteorites.

This one, although it started out the size of a bus wasn’t detected until the Russian people saw the fireball and its tail streaming through the sky at 33,000 miles an hour.

“It was too small to spot. It was only about ten to fifteen meters across.”

So how often do these hit the earth? the professor says one this size maybe every decade, but usually they fall in the ocean with no consequence.

The U.S. had a brushing.

“There was one in the Western U.S. in the 1960s but that one skipped right out of the atmosphere.”