Astronomers caught off guard by Russian meteor strike

A meteor in Russia injured more than 1,000 people Friday.

A huge asteroid 150 feet across hurtled safely past Earth is moving away from the planet.

It was the closest known flyby for a rock of its size, passing within 17,000 miles. That's closer than some satellites.

The flyby occurred just hours after a much smaller meteor exploded above Russia's Ural Mountains. Astronomers say the two events were coincidental and the objects were traveling in opposite directions.

Researchers who study space, meteors, and asteroids didn't see the small one coming. The hit-and-miss day for the planet Earth, they say, is unprecedented.

They were watching a much bigger asteroid, half the size of a football field, which flew alarmingly close to Earth. A Purdue researcher says he has never heard or seen anything like it.

A fiery rock, perhaps as big as a school bus, streaking five miles a second across the Russian sky, turning it both brilliant and horrifying.

"No one predicted this one," said Purdue Professor Jay Melosh, as he rushed between radio and television interviews.

The meteor exploding miles above Russia's Ural Mountains shattered more than a million square feet of glass and injured more than 1,000 people.

"This is unprecedented," Melosh said. "This is the most damage done to a city by any meteor ever known."

Melosh was so busy collecting information on the Russian meteorite, he lost track of time as a much larger asteroid named DA14 was passing alarming close to Earth.

"It's 2 o'clock. It's passed. We're safe. Okay," said Melosh, smiling.

Asteroids are space trash. DA14 missed earth by 17,000 miles, which is just twice our planet's diameter at the equator. That may seem like a lot, but in the grand expanse of the universe, it counts as a near miss.

A website Melosh created helps public safety officials and others calculate the impact of stellar rocks. Had DA14 been on a slightly different path, it would have hit with the power of a mid-sized nuclear bomb.

"If that occurred right over Chicago, there would have been not much left of the downtown area," he said.

His website, Impact:Earth! appeared to be overwhelmed with users Friday afternoon.

In one day, Earth, the third rock from the sun, dodged the big one and luckily took a much smaller - but spectacularly damaging - hit from space.

Researchers say these smaller meteors strike earth several times a year, but usually in remote places, witnessed by few people, if anyone. They will be studying this one to determine where it came from, possibly from the larger asteroid.

The meteor was flying faster than 18,000 miles an hour, which translates to two laps around the Indianapolis Motor Speedway in just one second.