Spacecraft Sent to Inspect NASA’s Asteroid Crash Site Now Sees Both Space Rocks

The Hera spacecraft, a mission led by the European Space Agency (ESA), has sent back its first image showing the asteroids Didymos and Dimorphos as two separate objects instead of a single dot, according to Universe Today. Hera is following up on NASA’s DART mission, which deliberately crashed into the smaller of the two space rocks in 2022.

Hera, which launched in October 2024, is now about 1,280 kilometers (795 miles) from the pair. The two asteroids orbit each other as they travel around the Sun, and the system sits about 197 million kilometers (122 million miles) from Earth. ESA says the first detailed pictures of Dimorphos are due on Nov. 25.

A mission built around one asteroid pair

Hera is run by ESA in cooperation with NASA and the Japanese Aerospace Exploration Agency. Its job is to study what the DART impact did to Dimorphos and what that can teach scientists about deflecting an asteroid headed for Earth.

Universe Today reported that the larger asteroid, Didymos, is estimated to be 780 meters (2,559 feet) in diameter. Dimorphos is much smaller, at about 151 meters (495 feet) across.

Ian Carnelli, ESA’s head of the Systems Department and the Hera mission manager, said that for the first time the spacecraft is seeing through its own cameras the double asteroid system it was designed for. He said the views will get sharper as Hera moves closer. He described Dimorphos as the first object in the Solar System to have its orbit measurably shifted by human action.

How the story got here

• 2013: The Chelyabinsk meteor blew out windows and injured more than 1,500 people, mostly from broken glass. Universe Today cited it as one reason concern about asteroid threats keeps growing.
• September 2022: DART hit Dimorphos at 6.1 kilometers per second (3.8 miles per second). The impact slowed the asteroid’s orbit around Didymos by 32 to 33 minutes. The original goal was at least 73 seconds.
• October 2024: Hera launched toward the asteroid pair.
• Nov. 25, 2026: ESA plans to release the first detailed images of Dimorphos.

Researchers also observed a plume of debris, known as ejecta, rising from the surface of Dimorphos as far as 10,000 kilometers (6,214 miles) into space. Universe Today called the DART mission a resounding success.

What Hera and its two small probes will study

Besides studying the surface of Dimorphos after the collision, Hera will release two shoebox-sized CubeSats, named Milani and Juventas, because the main spacecraft cannot fly very close to the surface.

Milani will examine the minerals at the DART impact site up close. Juventas will use ground-penetrating radar to look about 100 meters (328 feet) beneath the surface of Dimorphos. Its goal is to find out whether the asteroid’s interior is solid rock or a loose rubble pile, which is what some researchers have proposed.

Why it matters for planetary defense

Governments and scientists around the world are paying more attention to planetary defense, according to Universe Today. The outlet linked that interest to growing awareness of how many asteroids cross Earth’s orbital path.

DART showed that a spacecraft can change the motion of an asteroid. Hera is meant to show how the asteroid itself responded: what it is made of, what its inside is like and what the crash did to its surface. Together, the two missions are expected to give scientists key insights into how a potential asteroid impactor could be deflected before it could cause widespread harm on Earth.

What happens next

Hera will keep closing in on the pair, and its pictures should improve as the distance shrinks. The next milestone is Nov. 25, when ESA says it will unveil the first detailed images of Dimorphos. Later, the two CubeSats will be deployed to take a closer look at the impact site and the asteroid’s interior.

Around Prague, based on reporting by Universe Today