Earth Avoids Collisions With Pair of Asteroids

Hugh Pickens writes "According to NASA, a pair of asteroids — one just over three miles wide — passed Earth Tuesday and early Wednesday, avoiding a potentially cataclysmic impact with our home planet. 2012 XE5, estimated at 50-165 feet across, was discovered just days earlier, missing our planet by only 139,500 miles, or slightly more than half the distance to the moon. 4179 Toutatis, just over three miles wide, put on an amazing show for astronomers early Wednesday, missing Earth by 18 lunar lengths, while allowing scientists to observe the massive asteroid in detail. Asteroid Toutatis is well known to astronomers. It passes by Earth's orbit every four years and astronomers say its unique orbit means it is unlikely to impact Earth for at least 600 years. It is one of the largest known potentially hazardous asteroids, and its orbit is inclined less than half-a-degree from Earth's. 'We already know that Toutatis will not hit Earth for hundreds of years,' says Lance Benner of NASA's Near Earth Object Program. 'These new observations will allow us to predict the asteroid's trajectory even farther into the future.' Toutatis would inflict devastating damage if it slammed into Earth, perhaps extinguishing human civilization. The asteroid thought to have killed off the dinosaurs 65 million years ago was about 6 miles wide, researchers say. The fact that 2012 XE5 was discovered only a few days before the encounter prompted Minnesota Public Radio to poll its listeners with the following question: If an asteroid were to strike Earth within an hour, would you want to know?"

Comments

Tunguska?

[abies]

Actually, we are. A 50-165 foot asteroid can sneak up on us, but that isn't going to do much. It has less energy than the 9.0 Fukushima Earthquake, which killed ~10,000 people.

And how much energy from earthquake goes into actual surface damage? I was under impression that vast majority of it is used to shake rocks up and down, which is quite different from releasing same energy in something similar to surface nuclear strike.

I think we should be comparing it to Tunguska event rather than earthquakes. Imagine Tunguska happening over one of densly populated areas. I don't think that it would end up being 2-hours news.