LaSexta reported that ESA had scheduled Hera’s initial close-characterization phase at the Didymos–Dimorphos system for November 4, 2026, with the first proximity maneuver set for 01:00 GMT. The mission is designed to examine how NASA’s 2022 DART impact affected Dimorphos and what the asteroid pair can reveal about deflecting asteroids with a spacecraft impact. The reported schedule marks a planned mission phase, not a new scientific result.
For earlier context on Hera’s planned arrival, see NeoTeo’s report on the Didymos encounter.
What Hera is meant to learn from DART
Hera’s planned investigation covers the size, mass, composition and orbital dynamics of Didymos and Dimorphos. It also aims to map Dimorphos’s impact crater and study material thrown out by the collision. Those measurements are intended to help explain the consequences of the DART impact and inform future kinetic-impact deflection efforts.
LaSexta reported that post-impact data indicated Dimorphos’s orbital period had shortened by 33 minutes after DART struck it in September 2022. That is a reported DART result Hera was meant to investigate further, not a measurement from Hera. An orbital period is the time Dimorphos takes to circle Didymos.
The planned approach involves successive flybys about 25–30 kilometers from the asteroids. LaSexta also reported that Hera imaged Didymos and Dimorphos separately from 1,280 kilometers on October 18, 2026, before the scheduled start of the close-characterization phase.
Juventas and Milani have different roles
The two CubeSats carried by Hera are assigned complementary investigations. Juventas is intended to study Dimorphos’s weak gravity and use radar to probe beneath its surface. Milani is assigned to collect fine dust around the asteroid, which could offer clues about its composition and history.
ESA’s English-language animation illustrates the planned mission and the two CubeSats’ tasks.
Hera’s maneuvers took place at different stages
El Debate reported on March 17, 2026, that Hera had completed its second deep-space maneuver, using 123 kilograms of hydrazine and changing the spacecraft’s velocity by 367 meters per second. The report said the maneuver tested systems needed for the later braking and encounter operations.
LaSexta separately reported that a maneuver sequence beginning October 2 reduced Hera’s relative speed from 285 meters per second to 1 meter per second. That approach sequence and the earlier deep-space maneuver were distinct events; their speed figures describe different operations.
