Asteroid With Force Of 10 Atomic Bombs Exploded Above Earth, And We Didn't Even Know Is Scary

Asteroids are just fine when they stay in space, but the minute they come hurtling towards Earth we run scared. We know how massive they are, how much destruction they can cause, so it's only natural.

Except, when a massive one struck us last month, you missed it.

NASA

As it turns out, on December 18 last year, the second-largest asteroid to hit Earth in 30 years came plummeting towards us. On a direct course for impact, the rock was doing a blistering 32km/s at a very steep angle.

Thankfully for us though the meteorite, which was several metres long, exploded before it hit us, going up in a fireball about 25.6 km above the Earth's surface.

The explosion however had an impact energy of 173 kilotons. To compare, the bombs dropped on Hiroshima and Nagasaki had yields of 15 and 20 kilotons respectively.

"That was 40% the energy release of Chelyabinsk,"said Kelly Fast, the near-Earth objects observations program manager at NASA, referring to the major meteorite hit in Russia back in. "But it was over the Bering Sea so it didn't have the same type of effect or show up in the news,"

It was actually the US Air Force that first detected the fireball in the sky thanks to its satellites. The information was then passed on to NASA, who managed to grab some pictures. See the fireball below?

A picture snapped by a Japanese satellite

Wait, you don't? Well, look closer...just near the center...that little blip...

Yup, that's why you never knew about the asteroid. Well, that and the fact that the Earth doesn't have a meteor detection system yet. NASA has been working on one and hopes to be able to track 90 percent of all near-Earth objects larger than 140 m by 2020.

One problem with that is objects smaller than that might be harder to track out in space. Unfortunately, though possibly less damaging, they're also more frequent than other meteorite strikes.

In the meantime though, the US space agency has also been working on a plan to deal with the asteroids they do spot that seem to be heading for Earth. They're just going to shoot them to knock them off course, like a giant game of marbles in space.