An Asteroid Will Zoom By Earth, But We Don’t Know How Close Yet
published during a waning crescent moon.
03/03/2016
asteroid

Credit: NASA/JPL-Cal Tech

Lots of things hurdle through space, meaning that sooner or later, a curious space rock will take a peek at Earth. And that’s why NASA, like a stern museum guard, keeps its eye on onlookers, lest one lean in a little too close.

Next week a saucily named asteroid, 2013 TX68, will pass by Earth, but it’s of no concern to our safety. What it is, however, is a near-Earth object, a term that refers to comets and asteroids that were beguiled with some gravity from our neighborhood. The Center for Near-Earth Object Studies (CNEOS) has kept tabs on hundreds of them for years.

At 100 feet, asteroid TX68’s diameter is about the length of a basketball court — or a whale, if you’re still lamenting that poor, sweet guy that fell from the skies in Hitchhiker’s Guide to the Galaxy.

It actually first made a blip a few years ago (hence the 2013 in the name). But at 1.3 million miles away, it wasn’t visible for long, so astronomers won’t know how closely it passed until after it dimmed from view.

While it seems like something that size and that close would be easy to predict, consider this scenario that Slate’s astronomy blogger Phil Plait has outlined before:

“Think of it this way. Imagine you’re an outfielder in a baseball game. You see the pitcher throw the ball and the batter swings. It’s a hit! But one-tenth of a second after the batter makes contact, you close your eyes. Now, based on the fraction of a second you saw the ball move, can you catch it?”

Basically, CNEOS needs more data, which it’ll obtain during the March 8th flyby. The latest prediction pinpoints the asteroid at about 3 million miles from Earth, but it’ll likely be even farther than that.

The organization also hastened to add that TX68 won’t be a threat for another century after initial reports showed that it only had a 1 in 250 million chance of impact. So we can take a collective, slightly hesitant sigh of relief. In the meantime, for the telescope-inclined, here are some other close encounters that are coming up.