NASA

If an asteroid was shooting towards Earth, what would our options be?

Sure, we could send up a ragtag team of miners to drill into the asteroid, plant a nuke and blast it to smithereens.

But if NASA has its way, we won't need to train miners to be astronauts -- it has other plans to deflect those deadly asteroids. (A lucky thing too, because it makes far more sense to teach already-trained astronauts to use a drill rather than putting miners through astronaut school, but that's another matter entirely).

NASA is prepping for a (potential) doomsday outcome with the Double Asteroid Redirection Test -- a mission that will test whether we can crash a spacecraft into an asteroid and knock it off course, thus saving humankind and preventing us from ever sending Bruce Willis into space.

In this week's episode of Watch This Space , we take a look at the DART mission to 65803 Didymos -- a binary asteroid (complete with its own companion "moonlet") that's currently orbiting the sun out past Earth.

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According to NASA, the moonlet (or "Didymoon" as it's been nicknamed) is a perfect example of an asteroid of the size and type that could crash into Earth. So, the space agency wants to send its DART spacecraft up there as early as Dec. 2020 to blast towards the 150-metre-wide moonlet and crash into its surface.

Imagine it like a game of pool. If you need to knock the 8 ball in the corner pocket, you knock the cue ball into its side and it'll shoot off on an angle. By sending its cue ball careening into the moonlet, NASA will measure how the impact changes the moonlet's momentum and hopefully get a better idea of how asteroids can be redirected in future.

To learn more about the DART, the partner mission being run by the European Space Agency and what all this has to do with Elijah Wood and the film "Labyrinth" (there are connections, we promise) then check out this week's episode of Watch This Space. You can get your space fix every other Friday with new episodes, or catch up with the whole series on CNET or YouTube.