Double Asteroid Redirection Test

According to a press release, Hicks' main area of focus was the physical properties of comets and asteroids.

He worked on the DART, the Double Asteroid Redirection Test, NEAT, which is the Near-Earth Asteroid Tracking Teams, as well as the Dawn mission and the NASA Deep Space 1 mission.

By all accounts, Hicks was a well-established and well-accomplished scientist with over 80 papers to his name.

Then in 2023 something changed.

What have we done when we landed on the asteroid? It seems like we set off some sort of a detonation, right, as an experiment when we landed on a comet?

Um, you might be, uh, mixing that with another mission, because there was the Philae mission where we actually had a lander, and then there was what was called the DART mission, where we actually sent impactor on purpose.

This was actually two asteroids orbiting each other, and this was actually a test of a defense mechanism for Earth.

The idea is we can hit one asteroid, and we can see how much it deflects it from that impact by seeing what happens to the orbit of these two bodies around each other.

And since they're orbiting, we can do lots of good measurements.

So this was an experiment to basically see, hey, if we use impactors, will that save the world? And that was the DART mission from a couple of years ago at this point, and successful mission, I should say.

It was actually even more successful than expected.

I just realized I did it.

The asteroid fills the camera frame.

On September 26th, 2022, DART closed on Dimorphos, a small asteroid moonlet that did not threaten Earth.

Its camera transmitted images until the planned collision interrupted the signal.

Now, in a fictional inland community in the southeastern United States, a warning says a catastrophic impact is 72 hours away.

The safest first action is to confirm current official instructions for this location.

The dangerous mistake is fleeing toward an unverified destination simply because it is farther away.

DART was a test.

This countdown is hypothetical.

We're going to have a map of all these planets long before we can get there.

In September, the DART mission, so this is the Double Asteroid Redirect Test, Called that because it's actually a binary asteroid system.

So Didymos is this asteroid that flies relatively close to the Earth.

It's not huge, 780 meters across.

And actually, I said, I talked to you two years ago in preparation for a Real Science Radio interview.

I talked to her about the DART project.

And I said, I talked to you two years ago on this.

Well, we talked about it.

She's an MIT engineer for planetary science.

And so I said, it aerobrakes, and it all comes together as a loosely held rock pile.

And in the case of her project, which is the DART project, the Didymus Dimorphos, there's a Didymus mother asteroid.

Dimorphos was a moon that we smacked into with the DART mission probe that smacked into it to change its orbit.

Since then, Paul has served as a bridge between JAXA and NASA, helping the Hayabusa 2 and OSIRIS-REx teams share some really hard-won lessons about landing on boulder-covered worlds.

He's been on both of those science teams, on the Double Asteroid Redirection Test or DART investigation team, and he has an asteroid named after him, 8139 Paul Abel.

Hi, Paul.

Thanks for joining us.

or after the ordinary chondrite-type meteorite.

So it's a very common type of material that we find on Earth in our terrestrial meteorite collections.

We see this in some of the materials from our own DART mission that went to Didymos and Dimorphos It's very similar to the type of material type that is thought to be making up the asteroid Apophis, which is going to pass by here in 2029.

Right.

Well, sort of, maybe.

The age of asteroid deflection is really with us now after the success of NASA missions like DART and Deep Impact.

China is planning to launch an as-yet-unnamed asteroid deflection mission, and otherwise there are a lot of good ideas out there about how to either deflect or fragment an asteroid on a seeming collision course with Earth, and none of them involve attaching rocket engines.

And here's a fun fact for you.

However, like painting, this method will only very slightly modify an asteroid's trajectory, so you have to start with a lot of lead time, particularly for larger asteroids.

So if you don't have a lot of lead time, there's the kinetic impact method, where you crash something into the asteroid, imparting a kinetic energy which is derived both from the mass and the velocity of the thing that hits the asteroid.

This was measurably successful with the DART mission in twenty twenty-two.

So with this method, you can be confident of achieving a change in the asteroid's trajectory, but it's still not ideal for steering the asteroid onto a particular trajectory, since the effect of each impact will be a bit unpredictable.