Europe’s Hera spacecraft has captured its first close-up view of the Didymos binary asteroid system, revealing the battered backside of the main asteroid from 37 miles away.
Hera Nears the Asteroid System
The European Space Agency mission is designed to do a sort of crash scene investigation following NASA’s DART mission, which served as the first planetary defense rehearsal.
The two-year transit included a Mars gravity assist flyby on March 12, 2025, which brought the spacecraft within 5,000 kilometers of Mars and allowed for a flyby of the moon Deimos at approximately 300 kilometers, providing a chance to test the craft’s instrument suite. This maneuver brought the craft within 5,000 kilometers of Mars, and it also allowed a flyby of the moon Deimos at 300 kilometers to test the instrument suite.
The mission is currently operating at a distance of approximately 196.8 million kilometers from Earth, resulting in a one-way communication delay of about 11 minutes. Ian Carnelli, Hera’s Mission Manager and ESA Head of the Systems Department, said that the recent image release serves as a vindication of years of preparation. Before this approach, the spacecraft resolved the system as a single dot.
“With this image, the smaller Dimorphos asteroid becomes visible for the first time,” Michael Kueppers, Hera project scientist at the European Space Agency, said, and before this acquisition, the spacecraft was still resolving the Didymos system as a single dot. But now, even though Dimorphos is made up of only around one pixel in this initial image, it is clearly well separated from its parent body.”
DART Strike Altered Didymos Moonlet Orbital Period
That high-speed strike blasted debris thousands of kilometers into space and shortened the moonlet’s orbital period around Didymos by about 33 minutes.
Researchers currently lack data on whether the impact created a distinct crater or fundamentally altered the shape of the 151-meter-wide moonlet, which is roughly the size of the Great Pyramid of Giza. Its larger companion, Didymos, measures approximately 780 meters in diameter, which is slightly smaller than the height of the Burj Khalifa.
Hera’s newly released image reveals the hemisphere of Didymos that NASA’s spacecraft never photographed before the collision. “This feels like looking at a whole new world.” Scientists suggest that some of these newly observed surface characteristics may originate from impact-ejected material traveling across the roughly 1.15-kilometer gap between the two bodies. The pair orbits at this distance, with Dimorphos circling its parent at about 18 centimeters per second.
Closing in on Didymos. ☄️ Our planetary defence mission Hera has captured its first close-up of the binary asteroid system, 60 km away, as it prepares to investigate the aftermath of DART’s historic impact with Dimorphos. Detailed images of both asteroids are coming on 25… pic.twitter.com/VJmlvAtNwi
Hera Mission Investigates Kinetic Impact Effectiveness
The study of these bodies extends to other nearby moons. For the Hera mission, researchers intend to use the spacecraft’s instrument suite, including the Asteroid Framing Camera capable of resolving features as small as one meter, to conduct a systematic crash site investigation.
This work aims to determine how effectively a kinetic impact can move an asteroid, providing a repeatable technique for future planetary defense. It provides a repeatable technique for future planetary defense.
Upcoming Detailed Imaging Schedule
As the spacecraft continues its gradual arrival, researchers anticipate significantly sharper visuals that will resolve Dimorphos in high resolution and locate the exact impact crater left by DART.
“We will unveil the first detailed images of Dimorphos — the first object in the solar system to have had its orbit measurably shifted by human action — on 25 November.” Ian Carnelli added that the image marked a significant milestone, noting that the team has exciting work ahead to systematically map the changes identified on both bodies.
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