All About Hera, ESA Spacecraft That Is Set To Become Next Planetary Defender After NASA's DART | EXPLAINED

European Space Agency's Hera mission has the goals of planetary defence, technology demonstration, and performing bonus science experiments.

New Delhi: After NASA's Double Asteroid Redirection Test (DART), the next planetary defence mission will be European Space Agency's Hera mission, which is scheduled to be launched in 2024. 

The Hera mission has the goals of planetary defence, technology demonstration, and performing bonus science experiments. 

The DART spacecraft, scheduled for launch on November 24, will collide with Dimorphos, the small asteroid satellite of Didymos, the primary asteroid of a binary asteroid system. This will demonstrate a method of asteroid deflection by changing an asteroid's motion in space. 

As DART departs for deep space, ESA will provide crucial ground support to the spacecraft, and will help deliver signals from the mission immediately after launch, ESA said on its website.

European Space Agency's Hera Mission

ESA's Hera spacecraft is designed to undertake a detailed survey of the consequences of DART's collision.

Ian Carnelli of ESA, who is overseeing the Hera mission, said DART and Hera were originally conceived on a coordinated double-spacecraft basis, with one mission to perform the deflection, and the other to perform precision measurements of the result, ESA mentioned on its website.

He added that the scientific consortium named Asteroid Impact and Deflection Assessment (AIDA) was maintaining the international collaboration of the two missions. 

After DART collides with the 160-metre-diametre Dimorphos in September 2022, certain parameters, such as the precise mass of Dimorphos, its internal structure, and the size and shape of the crater left by DART, will remain unknown. Therefore, the Hera spacecraft will head towards the Didymos binary asteroid system in November 2024, to begin its detailed 'crime scene investigation' of Dimorphos and Didymos in late 2026, according to ESA. 

A 'selfie-sat', known as the Light Italian Cubesat for Imaging of Asteroids (LICIACUBE), will be a part of the DART mission, and will observe the collision, witness the DART impact on Dimorphos, study the formation of the plume generated by the impact, and characterize its structure and evolution.

Since Hera will gather data by going near the asteroid, it will turn DART's impact experiment into a deflection technique which is well understood, and can be deployed if an asteroid, posing a real threat to Earth, advances towards the planet in future. 

Timeline Of The Planetary Defender Hera Spacecraft

In 2024, ESA's Hera spacecraft will be launched by the Ariane 6 rocket. 

In 2026, Hera and its two CubeSats, Milani and Juventas, will reach Didymos to begin Investigation of the aftermath of DART's impact. 

Hera is also equipped with an optical camera, a laser radar lidar (detection system which works on the principle of radar, but uses laser light), and a thermal infrared scanner.

Hera Spacecraft Will Deploy Shoebox Sized CubeSats

The Hera spacecraft will deploy a pair of shoebox sized CubeSats — Milani and Juventas — which will perform supporting observations.

The Milani CubeSat will make spectral surface observations, while Juventas CubeSat will perform the first radar soundings within an asteroid, a technique which will serve as a means of mapping the asteroid's topography, and conditions at its base.

Milani will use its hyperspectral imager (system which analyses a wide spectrum of light) to inspect the mineral makeup of the asteroid surface. 

The Otto Hydraulic Bremen in Germany is responsible for building the Hera spacecraft. GMV in Spain is overseeing the engineering model of Hera's precision guidance, navigation, and control system. This will guide the Hera spacecraft to and around the Didymos binary asteroid system.

The European Space Research and Technology Centre (ESTEC) technical centre in Netherlands, which is ESA's main technology development centre for spacecraft and space technology, is currently testing the radar prototype of Juventas, according to ESA.

"International cooperation is an essential element in planetary defense endeavours," Patrick Michel, Hera's Principal Investigator, said on the ESA website.