The probe took off aboard a SpaceX Falcon 9 rocket from Cape Canaveral, in the United States.

The Hera mission, ESA's first planetary defence mission, will study in detail the asteroid Dimorphos, whose orbit was altered in 2022 by the impact of a probe launched by the US Space Agency (NASA), as part of the DART mission.

Dimorphos, a natural satellite of the asteroid Didymos, was the first body in the Solar System whose orbit was altered by human activity.

The Hera probe intends to use its 12 instruments to gather data on Dimorphos, which will prove that changing the direction of a body's trajectory, such as an asteroid, is a reliable planetary defence technique.

The device will also study the properties of the two asteroids and place two small satellites in Dimorphos' orbit, which will observe its surface and conduct radar surveys, the first of which to do so on an asteroid.

The asteroid that the Hera mission intends to study is considered a "prototype" of the thousands of asteroids that could pose a collision risk to Earth.

In this mission, the Portuguese companies Tekever, GMV, FHP and Efacec were involved in the development of several technological and operational components, such as an instrument with 'laser' technology capable of measuring distances of up to 20 kilometres, thermal insulation and the probe's guidance, navigation and control system, and an innovative communication system between satellites, according to information from the Portuguese Space Agency.

The Hera probe is expected to reach its final destination, more than 177 kilometres from Earth, in December 2026, after flying past Mars in March 2025.

Dimorphos, which is 160 metres in diameter, orbits Didymos, a larger rocky body measuring 780 metres in diameter.

In 2019, as an ESA Member State, Portugal decided to contribute €2.8 million to the financial envelope of the mission, which cost €363 million.