Asteroid Close Call
by Jason Kendall
So, you may have heard about the meteor that streaked over Russia early this morning … but the big space event that we were expecting today is a near miss with an asteroid, and it’s not related at all to what happened in Russia!
At 3 pm Eastern time today, an asteroid half the size of a football field will pass by us — with no danger to Earth. It’ll be about 17,000 miles away.
However, since it’s passing very close to the Earth, we want to know more about this solar system neighbor. Asteroid 2012 DA14 might not have the flashiest or best name, but it’s the “rock star” of the moment. It’s very tough to see from anywhere in the USA. In fact, by the time it’s dark in the U.S., the asteroid will have moved away so far that only a large telescope will be able to see it. By large, I mean a telescope with at least a 12 or 15 inch diameter. That’s not the kind of thing you can run out to the store and buy off the shelf. So, only people in Europe and Asia and Australia will be able to see it with a small telescope.
Why did it come so close? Well, first, everything in the solar system orbits the Sun, going in the same way (counter-clockwise as seen from above), and the asteroids are no different. But not everything goes in circles. So, their paths cross. It’s like watching a NASCAR race. They all go around the track, but they pass and dodge each other, and if the drivers didn’t actively drive out of the way, the cars would hit each other. It’s kind of hard to steer a planet, so things just gotta go the way they go, and sometimes they get really close.
The vast majority of all the asteroids live in the Asteroid Belt between Mars and Jupiter. It’s like downtown Asteroidville. Jupiter, King of the Planets, occasionally bumps some of the asteroids from their happy home in the Asteroid Belt, and then they make a long trek around the Solar System. We know of about 40,000 asteroids in the belt, and can track about 3000 of them. They are staying out there quite happily. But there are a lot of Earth-Crossing asteroids that might one day hit Earth.
We keep track of asteroids not just to make sure they don’t hit us, but also, one day we might want to mine them for resources like platinum and iridium. One big iron asteroid could make a lot of computer parts, and there are companies that are starting up today that will try to do just that in a decade or so. Also, we can study asteroids to learn more about the solar system’s history. The Dawn Mission just finished orbiting the second largest asteroid Vesta, and is on to Ceres. We’ve learned a lot by looking up close for the first time at such an ancient world. In fact, all asteroids pretty much are like time capsules from the when the Sun and Earth and all the other planets are forming. If we could get samples, then we would know even more. (But we do, and they’re called meteorites!)
Here’s a cool video showing how it will pass by the Earth:
More on near-Earth Asteroids by the WISE Mission:
Dawn looking at Vesta and Ceres:
La Sagra Observatory, where the asteroid was discovered:
Jason Kendall is a New York City NASA Solar System Ambassador, and is nice enough to write stories about Space for HTE Kids’ News. If you have any questions about Space, he’s your man! Submit any questions to him below!