Normally, NASA likes its probes to make contact with other objects in space in a very controlled manner. You want to land a rover on Mars, not drop a rover on Mars, for example. The Double Asteroid Redirection Test (DART) is different. This time, NASA is going to stomp the ion pedal and just ram the damn thing with their spaceship, because fuck you, asteroid. Also, they’ll learn a lot about potentially diverting dangerous asteroids from becoming meteors that hit Earth. But mostly because they don’t like how that asteroid is looking at them.
You know the DART project is exciting because it’s in the Planetary Defence section of the NASA website, which sounds like part of a movie involving lasers and at least one astronaut tumbling away into space.
The DART spacecraft is a boxy, ion-engined kinetic impactor with interesting roll-out solar panels, and looks like this:
The ion engine is especially interesting, because it’s a first application of a propulsion system likely to be used on future spacecraft:
“The DART spacecraft will demonstrate the NASA Evolutionary Xenon Thruster – Commercial (NEXT-C) solar electric propulsion system as part of its in-space propulsion. NEXT-C is a next-generation system based on the Dawn spacecraft propulsion system, and was developed at NASA’s Glenn Research Centre in Cleveland, Ohio. By utilising electric propulsion, DART could benefit from significant flexibility to the mission timeline while demonstrating the next generation of ion engine technology, with applications to potential future NASA missions.”
The target asteroid is an interesting choice, because it’s really two asteroids. The asteroid is called Didymos, and is a binary asteroid, because it has its own little “moonlet,” a smaller asteroid that orbits Didymos. This moonlet is DART’s target.
Using the solar-powered ion engine and advanced autonomous targeting software, DART will ram itself into the moonlet, which will change the speed of the moonlet’s orbit around Didymos, a change that can be studied by telescopes on Earth.
Studying the change in the orbital path can help us figure out how to most effectively smack a potential Earth-impacting asteroid off course enough to miss our planet, where we not only keep our stuff, but is also the location of every Shake Shack known to humankind.
Also, like any good, modern fight, there will be a witness getting the whole thing on video, in this case a small Cubesat that will be released prior to impact and may or may not upload the footage to Worldstar.
Over at Vice, there’s a good interview with astronomer Andy Rivkin who gives a great explanation of the DART mission and what it hopes to accomplish:
So, yeah, take that, asteroid. That little punk moonlet has until November 24 to February 15 of 2022 to get its shit together, since that’s the current launch window for DART.