Mission to An Asteroid

DART's One-Way Trip to Crash into Dimorphos

Why are you seeing this now? Because last night, NASA shot DART, a 1,210-lb spacecraft, into an asteroid named Dimorphos. The mission ended successfully with a dead-center impact.

This was a first test for our Planetary Defense System. We are studying how to alter the course of asteroids heading at Earth. Dimorphos is a 530-foot asteroid around 7 million miles away that orbits another much larger asteroid, Didymos.

Click here to see NASA’s video of the actual impact.

We know the orbit of Didymos very well. and this collision will knock it into a new one. The orbital period will slow by anywhere from 7-60 minutes, and this will tell us how much energy DART was able to transfer to Dimorphos.

The energy transferred is important to know. Was it a squishy collision into loose rock, was it a sharp collision into hard rock, did it split the asteroid, …?

Knowing the characteristics of the collision will tell us how massive and fast future spacecraft will need to be if the day ever comes when we need to defend the Earth from an incoming asteroid.

And our telescopes will be able to look at the debris cloud and spectrally analyze the chemical composition of the asteroid.

A future European Space Agency (ESA) mission, Hera, will launch in 2024 and land on Dimorphos in 2026 to study the impact crater. It will tell us more about the collision and how much ejecta was launched into space.

Thanks for reading,

Ed