Meteor Explodes Creating Russian Fireball

A fireball that exploded over Russia Friday, injuring up to 1,000 people, was originally believed to be 50 feet in diameter before it later crashed through the ice in a frozen lake.

Scientists say it was a once-in-a-100-year event, estimated to be the biggest explosion since a 130-foot meteor exploded over Siberia in 1908, according to space.com and NPR.

The 1908 explosion took down 825 square miles of forest; Friday's explosion reportedly damaged hundreds of buildings.

Friday's meteor was coasting along at 40,260 mph upon entering the Earth's atmosphere and, upon the blast, broke windows and caused light structural damage to buildings in the Russian city of Chelyabinsk, according to Space. com.

Oddly, Friday's meteor strike came before an asteroid missed the planet.

NASA estimated a 150-foot-wide asteroid, 2012 DA14, came abuot 17,000 miles of earth, a close call when it comes to asteroids zipping by Earth.

So, what do we make of these events: one a close call; the other a direct hit?

And with all that stuff in space — flying rock and hurling meteors — why isn't our friendly planet whacked more often?

For an answer, Swampscott Patch turned to its resident Sky Guy.

That would be astronomer who designed the Sun Circle at Preston Beach and taught astronomy and physics at Marblehead High School.

Jim says the earth has one big thing going for it.

" ...  there is A LOT of space in space," he said. "People are under the notion that there is no wiggle room when these visitors from other parts of the solar system come by Earth."

The problem for Earth is that there is a statistical probability that it is going to get hit by one of these objects one of these days, he said.

"We just don't know when and that is why should be on the look out 24/7," he said.