King's College London

From rocky worlds to large gas giants, The European Space Agency’s (ESA) Ariel mission will observe around 1000 exoplanets, with the mission science led by King's College London through Professor Giovanna Tinetti, Vice-Dean (Research) of the Faculty of Natural, Mathematical and Engineering Sciences (NMES) and Ariel Consortium Principal Investigator.

But for the mission to succeed, the telescope assembly, scientific instruments, and supporting hardware needed to collect the data, must not only survive launch but remain fully operational after travelling millions of kilometres away from earth.

A structural model of the Ariel spacecraft’s payload, which houses this critical equipment, was put through its paces in a series of tests carried out at the UK’s National Satellite Test Facility (NSTF) to validate the design and integrity of all components.

The first challenge was acoustic testing. The intense acoustic environment of a rocket launch can shake spacecraft to their core, and in the NSTF this environment is recreated using an array of powerful speakers and amplifiers.

Next came mass properties testing, a crucial step to understand the payload’s total mass, centre of gravity, and moments of inertia with extremely high precision. These measurements tell engineers vital information about how the spacecraft will behave during launch and throughout its journey to orbit.

For Ariel, that journey will take it 1.5 million kilometres from Earth to its operational home. Knowing the spacecraft’s “resistance” to rotation is essential for fine-tuning how it will be controlled once in space.

Finally, the payload faced the most violent phase: vibration testing. Satellites and spacecraft must endure extreme vibrations during launch, and large shaker tables at the NSTF replicated these forces in three directions.

Passing these tests is a significant milestone for any mission. For the RAL Space Ariel team, who had spent months painstakingly assembling the payload, which was developed by a consortium of more than 50 institutes across 16 ESA countries and with contributions from NASA, the Japanese Space Agency (JAXA) and the Canadian Space Agency, seeing the structural model withstand these trials was a proud moment.

Professor Tinetti said:

"This result marks an important accomplishment in the construction of Ariel and a significant step forward in our journey to understand the planets in our galaxy.

“The success of this testing phase is a strong testament to the value of engineering research, and we're proud to have King's College London scientists supporting this vital work.”