Planetary Defence

Asteroids are ancient space rocks left over from the formation of the Solar System. They are thought to have brought complex molecules, and possibly early life, to Earth billions of years ago. Today, our planet's current inhabitants must learn how to keep themselves safe from any future impacts.

Through ESA’s planetary defence efforts, Europe is a fundamental contributor to a global planetary defence system that is capable of providing early warning of dangerous near-Earth objects (NEOs) larger in size, about three weeks in advance, and able to deflect asteroids smaller than 1 km if known more than two years in advance.

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[ Hera ]

27 DEAI. 2026

First light: Hera resolves two asteroids instead of one

The European Space Agency’s Hera spacecraft for planetary defence has resolved its two target asteroids separately for the very first time, revealing the binary nature of the Didymos system, currently some 197 million km away from Earth.

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[ Space Safety ]

07 DEAI. 2026

The Incredible Adventures of the Hera mission - the Space Detectives arrive

Meet Hera, our very own asteroid detective. Together with two CubeSats – Milani the rock decoder and Juventas the radar visionary – Hera is off on an adventure to explore Didymos, a double asteroid system that is typical of the thousands that pose an impact risk to planet Earth. After their two year cosmic roadtrip, Hera and its little CubeSat companions have finally arrived at Didymos and Dimorphos – the very first Solar System object to have had its orbit shifted by human action. Suitable for kids and adults alike, this episode of ‘The Incredible Adventures of the Hera mission’ explains what ESA’s asteroid detective and its CubeSat assistants will be up to once they arrive, and precisely how they are going to say goodbye to each other – letting the CubeSats begin their close-up exam of this historic space rock.

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[ Operations ]

23 MEÁN. 2026

First switch on for ESA-JAXA Ramses asteroid mission

The European Space Agency’s and Japan Aerospace Exploration Agency’s Ramses planetary defence spacecraft has been turned on for the first time by its prime contractor – marking a major milestone in its time-critical development schedule.

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[ Operations ]

23 MEÁN. 2026

A hitchhiker’s guide to Hera’s target asteroids

Currently speeding through deep space at 12 km/s relative to Earth, ESA’s Hera spacecraft is due to reach its target Dimorphos asteroid this November. But if an astronaut were magically teleported onto the small-car-sized Hera upon arrival, what would they be seeing, and what would it feel like to walk on the asteroid’s surface?

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