Hello, friends! Welcome to Our Place in Space: A to Z! For this year’s A to Z Challenge, I’ll be taking you on a partly imaginative and highly optimistic tour of humanity’s future in outer space. If you don’t know what the A to Z Challenge is, click here to learn more. In today’s post, D is for…
THE DART MISSION
So far this month, I’ve been telling you about things that I think will happen (or plausibly could happen) at some point in the distant future. But today, I’m going to talk about something that’ll happen in the not-so-distant future. Something that will happen in the very near future, actually. Later this year, in fact! In late September or early October of 2022, a NASA space probe named DART will deliberately crash into an asteroid named Dimorphos.
Dimorphos is a relatively small asteroid orbiting a much larger asteroid named Didymos. Basically, Dimorphos is Didymos’s moon. These two asteroids will be passing fairly close to Earth later this year. Now I want to be 100% clear about this: neither Didymos nor Dimorphos are going to collide with our planet. We are in no danger. But these asteroids will be coming close enough that we could do a little experiment—an experiment to see just how well we could defend our planet from a dangerous, mass-extinction-causing asteroid, should such an asteroid ever come our way.
DART stands for Double Asteroid Redirection Test. As you can see in the highly technical diagram below, the plan is for the DART spacecraft to have a head-on collision with Dimorphos.
This head-on collision should cause Dimorphos to lose some orbital momentum, which should alter Dimorphos’s orbit around Didymos. How different will Dimorphos’s new orbit be? Hard to say. The exact angle of impact… the astroid’s mineral composition… the amount of debris produced by the collision… all of these things may factor into what Dimorphos’s new orbit looks like.
Astronomers can do all the computer simulations they like, but until we throw a real life projectile at a real life asteroid, we won’t really know what will happen. Not with any kind of precision. Ergo, we need to do this experiment.
Looking once more into the distant future, I believe that humanity is going to spread out across space. Large numbers of people will eventually be living on the Moon and Mars, as well as on other planets and moons of our Solar System. But I also believe these humans in the distant future will take good care of the Earth. Among other things, they will know how to defend Earth from incoming asteroids and comets, so that what happened to the dinosaurs never has to happen again. And that capability—the capability to keep Earth safe from killer asteroids and comets—begins with a little NASA experiment scheduled to occur later this year.
Want to Learn More?
Here are a few papers that I’ve been reading about the upcoming DART Mission. This is where I got most of the information for today’s post: