Skip to main content

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.”

Editors' Recommendations

Georgina Torbet
Georgina is the Digital Trends space writer, covering human space exploration, planetary science, and cosmology. She…
See the weather patterns on a wild, super hot exoplanet
This is an artist’s impression of the exoplanet WASP 121-b, also known as Tylos. The exoplanet’s appearance is based on Hubble data of the object. Using Hubble observations, another team of scientists had previously reported the detection of heavy metals such as magnesium and iron escaping from the upper atmosphere of the ultra-hot Jupiter exoplanet, marking it as the first of such detection. The exoplanet is orbiting dangerously close to its host star, roughly 2.6% of the distance between Earth and the Sun, placing it on the verge of being ripped apart by its host star's tidal forces. The powerful gravitational forces have altered the planet's shape.

When it comes to understanding exoplanets, or planets outside our solar system, the big challenge is in not only finding these planets, but also understanding what they are like. And one of the biggest factors that scientists are interested in is whether an exoplanet has an atmosphere and, if so, what it is composed of. But, just like with weather here on Earth, exoplanet atmospheres aren't static. So the Hubble Space Telescope was recently used for an intriguing observation -- comparing data from an exoplanet atmosphere that had previously been observed, to see how it changed over time.

Hubble looked at planet WASP-121 b, an extreme planet that is so close to its star that a year there lasts just 30 hours. Its surface temperatures are over 3,000 Kelvins, or 5,000 degrees Fahrenheit, which researchers predict would lead to some wild weather phenomena. As it is such an extreme planet, WASP-121 b is well-known and has been observed by Hubble several times over the years, beginning in 2016.

Read more
How astronomers used James Webb to detect methane in the atmosphere of an exoplanet
An artists rendering of a blue and white exoplanet known as WASP-80 b, set on a star-studded black background. Alternating horizontal layers of cloudy white, grey and blue cover the planets surface. To the right of the planet, a rendering of the chemical methane is depicted with four hydrogen atoms bonded to a central carbon atom, representing methane within the exoplanet's atmosphere. An artist’s rendering of the warm exoplanet WASP-80 b whose color may appear bluish to human eyes due to the lack of high-altitude clouds and the presence of atmospheric methane identified by NASA’s James Webb Space Telescope, similar to the planets Uranus and Neptune in our own solar system.

One of the amazing abilities of the James Webb Space Telescope is not just detecting the presence of far-off planets, but also being able to peer into their atmospheres to see what they are composed of. With previous telescopes, this was extremely difficult to do because they lacked the powerful instruments needed for this kind of analysis, but scientists using Webb recently announced they had made a rare detection of methane in an exoplanet atmosphere.

Scientists studied the planet WASP-80 b using Webb's NIRCam instrument, which is best known as a camera but also has a slitless spectroscopy mode which allows it to split incoming light into different wavelengths. By looking at which wavelengths are missing because they have been absorbed by the target, researchers can tell what an object -- in this case, a planetary atmosphere -- is composed of.

Read more
James Webb investigates a super puffy exoplanet where it rains sand
Artistic concept of the exoplanet WASP-107b and its parent star. Even though the rather cool host star emits a relatively small fraction of high-energy photons, they can reach deep into the planet’s fluffy atmosphere.

Exoplanets come in many forms, from dense, rocky planets like Earth and Mars to gas giants like Jupiter and Saturn. But some planets discovered outside our solar system are even less dense than gas giants and are a type known informally as super-puff or cotton candy planets. One of the least dense exoplanets known, WASP-107b, was recently investigated using the James Webb Space Telescope (JWST) and the planet's weather seems to be as strange as its puffiness.

The planet is more atmosphere than core, with a fluffy atmosphere in which Webb spotted water vapor and sulfur dioxide. Strangest of all, Webb also saw silicate sand clouds, suggesting that it would rain sand between the upper and lower layers of the atmosphere. The planet is almost as big as Jupiter but has a tiny mass similar to that of Neptune.

Read more