Have you ever thrown a rock into a pond and watched the ripples roll away from where it landed? Now imagine something similar happening in space, but on a much larger scale. That’s exactly what happened when NASA’s DART spacecraft made history by changing the trajectory of a giant space rock hurtling through space.

DART mission makes history

In 2022, DART didn’t just create waves, it sent waves of debris into space. It strategically collided with the asteroid Dimorphos, causing a ripple effect that shifted its orbit around its larger sibling, the asteroid Didymos.

The interaction didn’t stop there. The collision caused an astronomical dust storm, a debris cloud that could soon become a little personal for us Earthlings and our rusty neighbor Mars. The latest models suggest that some of the smaller meteoroids from this debris could reach both Earth and Mars. But don’t worry. The shower of fragments won’t be catastrophic, but rather a sight that can be safely observed from our locale.

Planetary Defense Cooperation

The small moon Dimorphos, about 160 meters in diameter, orbits the larger Didymos in a so-called binary asteroid system. The DART spacecraft, or Double Asteroid Redirect Test, made contact with Dimorphos on September 26, 2022.

The result? Dimorphos’s orbit around Dimorphos was significantly shortened by half an hour. This was the first truly game-changing act of international cooperation in planetary defense.

Hera will investigate further

So who will clean up the mess now? The ESA Hera spacecraft. Scheduled to launch this October, Hera will arrive at Dimorphos to conduct a close-up “crash site inspection” following the crash of the DART mission.

“The DART collision provides a rare opportunity to investigate the distribution of debris on other celestial bodies because we know the location of the collision and it was observed by observers on the ground as well as by the Italian LICIACube deployed with DART,” said Michael Kueppers, Hera mission scientist and co-author of this exciting development.

Will DART debris reach Earth?

To understand how debris from Dimorphos’ impact might reach us, it’s important to estimate its speed.

“Our results show that debris with an ejection velocity of around 450 m/s is likely to reach the gravitational field of Mars within 13 years, while faster debris ejected at 770 m/s could reach its outskirts in just seven years,” explained Eloy Pena-Asensio, lead author of the study.

“Particles moving at speeds greater than 1.5 km/s can reach the Earth-Moon system in a similar time.”

But whether the debris actually reaches Mars or Earth depends on several factors. In fact, the location of the debris in the shock plume plays a decisive role.

Man-made meteor shower

“In the coming years, meteorite observation campaigns will be crucial to determine whether fragments of Dimorphos from the DART impact have reached our planet. If so, we will witness the first man-made meteor shower,” said Pena-Asensio.

As for other meteors, the largest will probably be about the size of a softball. These larger particles will burn up in Earth’s atmosphere, but they may make it through the thinner Martian atmosphere.

However, smaller particles moving at higher speeds have a chance of reaching the Earth’s atmosphere. But don’t panic. We have the time and resources to track the debris and ensure our safety.

DART’s mission statement

The significance of DART’s impact is not just about changing the paths of potential meteor showers or space debris, but also about the human spirit of curiosity, exploration, and conquering new frontiers.

“Our precise knowledge of the impactor’s location and properties in terms of size, mass and velocity, as well as our observations of the ejected material, allowed us to predict the long-term fate of material leaving the Didymos system,” said Michael Cooper.

Named after the Greek goddess of marriage, Hera is expected to begin exploring the asteroid pair in late 2026. According to ESA, the spacecraft will produce a high-resolution map of Dimorphos, providing valuable information for future asteroid deflection missions and science.