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Next-generation exoplanet hunter Plato goes through vacuum testing

The study of exoplanets, or planets outside our solar system, has exploded in the last decade. Thanks to missions like the Kepler Space Telescope and CHEOPS, we’ve discovered a trove of thousands of exoplanets — and the next phase in our understanding of these distant worlds is to learn more about them. Tools like the James Webb Space Telescope will study the atmospheres of exoplanets, and it will be complemented by an upcoming telescope from the European Space Agency (ESA) called Plato.

Plato is a next-generation exoplanet-hunting satellite, set for launch in 2026. To get the telescope and its systems ready for the rigors of launch and the harsh environment of space, Plato hardware is undergoing testing at ESA’s ESTEC Test Centre and at SRON, the Netherlands Institute for Space Research. Most recently, a test version of Plato’s payload module has been vacuum tested in a special vacuum chamber to ensure it can stand up to the space environment.

A test version of the payload module of ESA's exoplanet-detecting Plato spacecraft underwent a prolonged vacuum soak within Europe’s largest thermal vacuum chamber, to evaluate its endurance of space conditions.
A test version of the payload module of ESA’s exoplanet-detecting Plato spacecraft underwent a prolonged vacuum soak within Europe’s largest thermal vacuum chamber, to evaluate its endurance of space conditions. ESA-Remedia

The payload was placed into a space simulator for several weeks which recreates the extremely low pressure of space. Plato will be particularly reliant on its cameras for detecting exoplanets, with a total of 26 cameras on board, so these cameras needed to be checked in the vacuum environment as well. Over six weeks, a prototype of the camera was tested by being placed into a model of the spacecraft module called the engineering model.

“It turns out that all features of the Engineering Model function as expected,” said Lorenza Ferrari, the project manager, in a statement. “This is good news for Plato in general, and it also shows that our space simulator works extremely well.”

The next step is to check a version of all 26 cameras, which will be contained in a model called the flight model. This will check whether the cameras maintain their all-important accuracy during not only the cold conditions of space but also during the temperature variations experienced during launch.

“Located at the L2 Lagrange point, Plato (PLAnetary Transits and Oscillations of stars) will have 26 of these cameras pointing at the same target stars,” explained Yves Levillain, Plato’s Instrument System Engineer.” They will acquire images every 25 seconds — every 2.5 seconds for the two central cameras — for at least two years at a time to detect tiny shifts in brightness caused by exoplanets transiting these stars.”

Georgina Torbet
Georgina is the Digital Trends space writer, covering human space exploration, planetary science, and cosmology. She…
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