ESA’s Hera mission team congratulates its colleagues NASA’s DART mission team for their historical influence on the asteroid Dimorphos. Traveling at 6.1 km per second, the vending machine-sized Double Asteroid Redirect Test spacecraft struck the 160 m diameter asteroid at 01:15 EDT (00:15 BST) in the early hours of Tuesday morning in mankind’s first test ‘Kinetic Impactor “-Method of planetary defense.
Ian Carnelli, Hera’s Mission Manager, says: “To make contact with such a small target 11 million kilometers in space is in itself an impressive feat of engineering. A wonderful page in space history was written tonight. One we’ve all been looking forward to for many years. Today our thoughts are also with the late Prof. Andrea Milani, who first outlined this deflection test in 2004.
“Next follows a period of continued observation by ground- and space-based telescopes to determine whether the impact of DART has indeed achieved what was intended, and the orbit of the Dimorphos ‘moonlet’ around its parent asteroid Didymos with a diameter of 1 to move from 780 meters.
“In parallel, ESA and our industrial partners are continuing our work on the construction of the Hera spacecraft, which will be launched in late 2024 and begin its own journey to Dimorphos to conduct a close-up survey of the asteroid after impact. Hera will collect key information such as the size of DART’s crater, the mass of Dimorphos and its composition and internal structure. This additional data will help transform the DART deflection experiment into a well-understood, repeatable technique that could one day be performed in the real world.”
NASA’s DART and ESA’s Hera missions are supported by the same international teams of scientists and astronomers and take place as part of an international collaboration called AIDA – Asteroid Impact and Deflection Assessment. Defending the planet knows no borders and is a great example of what international cooperation can achieve.
The missions were launched together in the early years of the 21st centurySt In the late 20th century, when concerns about the destructive potential of approaching asteroids led to the creation of the first automated surveying systems, which led to ESA’s Near Earth Object Coordination Centre, NEO CC and NASA’s Post System.
But the space scientists working on the system realized that identifying asteroid threats wasn’t enough; They also had to find a way to counter this threat.
Ian explains: “Mathematician and astronomer Andrea Milani of the University of Pisa – a planetary defense pioneer who sadly passed away in 2018 – came up with the idea of a two-spacecraft mission, which he dubbed ‘Don Quixote’: one spacecraft would crash into an oncoming one asteroids while the other observer spacecraft would measure the degree of deflection.”
Eventually the concept was internationalized, with NASA adopting what would evolve into DART. ESA’s Hera will follow its predecessor into space in 2024 and arrive at Dimorphos two years later. Its target asteroid will be of particular importance as the first body in the solar system whose surface and orbit have been measurably altered by human intervention. Its name comes from Greek and means “having two forms”.
ESA’s Hera spacecraft is taking shape
Hera’s payload module is currently taking shape OHB in Germany, while the drive module is being completed at Avio in Italy, with companies and institutions in 17 European countries making their own contribution to the mission – such as GMV in Spain, the development of the automated guidance, navigation and control system that will allow the spacecraft to safely navigate through the dual asteroid system, much like a self-driving car.
The desk-sized Hera is packed with instruments, with its optical Asteroid Framing Camera complemented by thermal and spectral imaging cameras, and a laser altimeter for surface mapping. Hera is also three spaceships in one, as it will also bring a pair of shoebox-sized “CubeSats” near Dimorphos.
The Juventas CubeSat will perform the first-ever radar probe of an asteroid, while also carrying a gravimeter and accelerometer to measure the body’s extremely low gravity. The other CubeSat, Milani – named after the inventor of AIDA – will perform near-infrared spectral imaging and study asteroid dust.
The CubeSat pair will remain in contact with their Hera mothership and each other via a novel inter-satellite link system to gain experience monitoring multiple spacecraft in exotic zero gravity before finally landing on Dimorphos.
Ian concludes: “Thanks to DART we had an enticing glimpse of our destination, now we can’t wait to go back and explore it in depth to find out how the impacts have transformed it and to help make the Earth a safer place place in the process.”