A hundred years ago ...

On this day in 1908, an asteroid paid a visit to Siberia. Traveling at an estimated 10 miles per second, it energetically disassembled itself approximately four to six miles above the ground. The resulting blast, with an estimated energy equivalent of 10-15 megatons of TNT, wiped out eighty million trees, and pretty much everything living in an 800 square mile radius.

(Photo: Soviet Academy of Science 1927 expedition, led by Leonid Kulik. Source: WikiPedia.)

The 1966 edition of the Guinness Book of World Records estimated that had the asteroid struck 4 hours, 47 minutes later, that it would have hit St. Petersburg, the capital of imperial Russia, rather than the middle of sparsely populated Siberia.

A close call, one hundred years ago.