In August, the JUICE satellite will execute a spectacular manoeuvre, unprecedented in the history of space exploration.

For the first time, a satellite will harness the gravitational forces of both the Earth and the Moon during a flyby to adjust its course towards its final destination:

Jupiter, the giant of our solar system.

Pushing the boundaries of physics on its journey to Jupiter

On the 19th and 20th of August, this complex manoeuvre will involve bending the spacecraft’s trajectory, slowing it down, and providing the necessary boost to fly past Venus in August 2025. This extreme manoeuvre requires precision and technological perfection.

  • Text:Amanda Chapman-Stavn / KONGSBERG

    Photo:ESA / Los&Co

JUICE, or the JUpiter ICy moons Explorer, is one of Europe’s most ambitious space missions. Its goal is to explore Jupiter and its icy moons, Ganymede, Callisto, and Europa, in the search for signs of life. With a journey spanning nearly ten years and an expected arrival at Jupiter in 2032, JUICE is equipped with ten advanced scientific instruments. These include spectrometers, radar, and magnetometers, which together will provide us with an understanding of the conditions on Jupiter's moons like never before.

KONGSBERG-technology onboard

A crucial part of this groundbreaking mission is the technology provided by Kongsberg Defence & Aerospace – the Solar Array Drive Mechanism (SADM). This component is critical to ensuring that JUICE receives sufficient energy from its solar panels, even when the satellite is so far from the Sun that sunlight is 25 times weaker than on Earth.

The solar panels, covering a total area of 85 square metres, must be rotated precisely and flawlessly to ensure a constant energy supply, including when the spacecraft moves away from the Sun and temperatures rise, such as when passing Venus.

I am incredibly proud to be part of the team that has delivered such an advanced system for an extremely demanding mission.

The development, production, and testing of equipment with such stringent performance and reliability requirements have been a significant but positive challenge. 

Stein Hollung, Programme Director for Space Products at Kongsberg Defence & Aerospace.

The satellite must also operate flawlessly under extreme conditions: relentless radiation, temperatures ranging from a frigid -230 to +250 degrees Celsius, and severe mechanical stresses.

Kongsberg Defence & Aerospace was contracted by Airbus in Toulouse in 2016 to supply this essential technology. 

In addition to SADM, we have also delivered Attachment & Release Mechanisms and Level Conditioners for the Ariane 5 rocket. 

The attachment mechanisms connect the booster motors to the rocket body and transfer the forces that lift the rocket, while the level conditioners monitor the fuel levels in the tanks.

An extreme manoeuvre with careful monitoring

The extreme manoeuvre is not only technologically impressive but also necessary. To reach Jupiter, JUICE must gain sufficient speed without using vast amounts of fuel. By utilising the gravitational forces of both the Earth and the Moon, JUICE can adjust its trajectory without additional fuel consumption, which would otherwise be required to enter orbit around Jupiter. This will be the first time a spacecraft performs such a flyby of both the Earth and the Moon, using the gravitational pull of two celestial bodies simultaneously.

The operation will be closely monitored from ESA's control centre in Darmstadt, Germany, with support from ground stations around the world, including Kongsberg Satellite Services' (KSAT) ground station in Svalbard. Between the 17th and 22nd of August 2024, operators will ensure that every movement of JUICE is precisely controlled, and minor adjustments will be made to ensure that the extreme manoeuvre is executed to perfection.

As an engineer with over 20 years of experience with space products, Hollung shares his excitement about the manoeuvre itself.

"A tremendous amount of planning goes into such a manoeuvre. Using gravity to slow down and enter the correct orbit requires unparalleled precision. It's especially exciting that this manoeuvre is being performed for the first time, with KONGSBERG-technology onboard."

With JUICE on its way to Jupiter, humanity takes another step forward in exploring the outer solar system.

"The JUICE project has required enormous resources, and large parts of the organisation have been involved. I am proud of the team behind the advanced, and exciting, work that has been carried out," Hollung concludes.

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