ESA's Hera Completes Major Deep‑Space Burns, On Track To Reach Didymos In November 2026

The European Space Agency's Hera spacecraft has completed a major deep‑space maneuver that places it on course to rendezvous with the Didymos binary asteroid system in November 2026. Launched on a SpaceX Falcon 9 in October 2024, Hera's primary objective is to study Dimorphos — the smaller body struck by NASA's DART mission in September 2022 — and to characterize the aftermath of that impact.

About a year into its cruise, Hera performed a Mars flyby in March 2025. That encounter let the spacecraft exercise autonomous, vision‑based navigation while its cameras observed Mars' moon Deimos, and it adjusted Hera's trajectory toward Didymos.

Three Main Burns Plus A Correction

During a carefully planned campaign in February and March, mission controllers executed three principal engine firings plus a smaller correction burn over roughly four weeks. "We divided the deep‑space maneuver into three engine burns, plus one much smaller correction maneuver, carried out over a period of around four weeks," said Francesco Castellini of ESA's Flight Dynamics team at the European Space Operations Centre in a March 17 statement.

"This is the Hera mission's largest maneuver in terms of fuel consumption, and we used it to test all of the systems that we will need during the braking and rendezvous maneuvers later this year as we arrive at Didymos."

The burns consumed 123 kilograms (271 pounds) of onboard hydrazine and produced a velocity change (delta‑v) of 367 meters per second (1,204 feet per second) — about 821 mph (1,321 kph). ESA noted the delta‑v is "comparable to an object accelerating from stationary to supersonic flight." ESA's Estrack deep‑space antenna network confirmed the success of the maneuver.

ESA's Hera mission conducted a deep space maneuver in February/March 2026 to align the inclination of the spacecraft’s orbit around the sun with that of its destination — the Didymos binary asteroid system. | Credit: ESA

Preparing For Arrival

Ground teams are now uploading extensive software updates and preparing for arrival at the Didymos system. Hera will begin a series of precision burns in October to transition from its interplanetary cruise profile into an approach trajectory for the binary pair.

The spacecraft carries 12 scientific payloads and will spend at least six months conducting a phased investigation: initial global surveys, deployment of two CubeSats (Milani and Juventas), followed by detailed mapping and a close, experimental inspection of the DART impact crater from an altitude of about 1 kilometer (0.62 miles).

Scientific Goals And Context

Hera's detailed observations aim to turn DART's single kinetic‑impactor test into a repeatable, scalable method for deflecting hazardous asteroids. Hera will also perform the first systematic survey of a binary asteroid system, complementing data from other international small‑body missions such as NASA's OSIRIS‑APEX, JAXA's Hayabusa2 and China's Tianwen‑2.

Scientists recently reported that DART's impact on the roughly 170‑meter (560‑foot) Dimorphos unexpectedly altered the orbit of its larger companion, Didymos (about 850 meters / 2,788 feet across). That surprising result could provide fresh insight into binary asteroid dynamics and how such systems respond to impacts.

With the deep‑space maneuver successfully completed and final approach activities planned for later this year, Hera is positioned to deliver a rich set of measurements that will inform planetary defense strategies and our understanding of small‑body systems.