In the context: Our planet can be a beautiful place at times, but one day, a giant asteroid may simply decide to prematurely end our collective fun. Compared to the size of other astral bodies, it does not take much space rock to damage the planet – even a 150-meter asteroid is large enough to pose a “serious threat” to Earth. That’s why NASA is working on DART: a double asteroid redirection test.
Since it is impossible to completely stop the asteroid’s momentum with our current level of technology, and since we have yet to build a sci-fi energy shield around the entire planet, deflection is the next best option in the arsenal of mankind. And the deflection is exactly what DART hopes to implement.
Essentially, DART will use what NASA calls a “kinetic impact” technique to send a spacecraft into the great void, with the specific intent of hitting the target asteroid. NASA hopes this will knock potentially dangerous asteroids so far away that Earth is no longer on their trajectory. In any case, this is a long-term goal. In the short term, NASA needs to make sure their technology works: this is where its first proper test comes in.
NASA will launch its DART spacecraft in the early morning hours tomorrow or tonight, if you’re an owl like me. The event kicks off November 24 at 1:21 am ET. The asteroid DART will aim for is known as Didymos, with a main body 780 meters across. The smaller body is about 160 meters and will be the target of the demonstration.
DART will launch aboard a SpaceX Falcon 9 rocket and take off from Vandenberg Space Force Base in California. After DART successfully parts with its launch vehicle, it will travel to its destination and is expected to arrive sometime in September 2022.
It should be clear to us that, according to NASA, Didymos is No a threat to Earth right now, which is why the organization wants to use it as a glorified test subject. If NASA’s calculations are correct, a DART collision with Didymos’s “moon” will change the speed of its orbit around the main body by “a fraction of one percent.” This corresponds to a change in “orbital period” of several minutes, which should make it observable and measurable with telescopes on Earth.
The ability to observe Didymos’s younger brother is critical to the success of the mission. NASA will rely on visual cues, such as how often moonlight obscures the light that bathes Didymos, to determine if it has been knocked off course.
It will be a while before we ordinary people get this data, but it’s an exciting time nonetheless, and we can’t wait to see if the DART mission is successful. Let’s hope nothing happens with the launch tonight.