CHEOPS Space Mission extended

Following the remarkable scientific achievements of the space telescope CHEOPS, the European Space Agency (ESA) has decided to extend the mission once again. The space telescope, which was built at the University of Bern and whose science operations center is located at the University of Geneva, will now continue to operate until the end of 2029. This decision underscores the outstanding performance and scientific value of CHEOPS in exoplanet research.

CHEOPS is a joint mission of the European Space Agency (ESA) and Switzerland, led by the University of Bern in collaboration with the University of Geneva. Under the leadership of the University of Bern and ESA, a consortium of more than a hundred scientists and engineers from eleven European nations spent five years building the satellite. The CHEOPS science operations center is located at the Department of Astronomy of the University of Geneva. Since its launch from the European Spaceport in French Guiana on December 18, 2019, CHEOPS has revealed the properties of numerous fascinating planets outside our solar system, known as exoplanets. After ESA had already extended the mission by three years in 2023, its Science Programme Committee has now decided on a further extension until the end of 2029.

Dr. Christopher Broeg, principal investigator of the CHEOPS mission and head of the CHEOPS consortium at the Center for Space and Habitability (CSH) at the University of Bern, explains: “The precision of CHEOPS has exceeded all expectations, and the space telescope has become a key component in the arsenal of exoplanet research for astronomers in Europe and worldwide. It bridges the gap between early discovery missions such as Kepler and TESS and next-generation missions such as PLATO, as well as missions designed to characterize exoplanet atmospheres, such as JWST and, in the future, Ariel. The renewed extension of the mission is proof of this and of CHEOPS’ scientific success.” Dr. Andrea Fortier, CHEOPS Mission Manager and from the CSH at the University of Bern as well, adds: “We can now look forward to three and a half more years of exquisite science and fascinating discoveries.”

An unorderly planetary system and a deformed exoplanet

Prof. David Ehrenreich of the Department of Astronomy at the University of Geneva is heading the international team of over a hundred scientists involved in analyzing the mission data. He says: “We are delighted with the scientific insights we have gained thanks to CHEOPS. For example, CHEOPS’s discovery of a new planet orbiting the star LHS 1903 challenges the prevailing theory of how planets are arranged within a system.”

With the help of CHEOPS, the deformation of an exoplanet was detected for the first time. Prof.  Monika Lendl from the Department of Astronomy at the University of Geneva and CHEOPS Mission Scientist explains: “Although the planet WASP-103b had already been observed previously using the NASA/ESA Hubble Space Telescope, it was only high-precision measurements taken with CHEOPS that led to an astonishing discovery. Based on small anomalies during the planet’s transit in front of its host star, we were able to determine that it is literally being pulled apart by strong tidal forces. Its shape resembles a rugby ball rather than a sphere."

Over the next years, CHEOPS is set to build on these successes. “With the mission extension, we can continue long-term observation programs, examine new planetary systems in detail, and target rare phenomena that can only be discovered with a long-term approach,” says Broeg.

Synergies with international space missions

Close coordination with other space missions plays a central role. CHEOPS already works in tandem with telescopes such as the James Webb Space Telescope (JWST): While CHEOPS determines the size, orbit, and sheds light on the structure of exoplanets with its precise brightness measurements, JWST’s spectrographs provide a glimpse into their atmospheres. “Thanks to CHEOPS, we can identify particularly exciting targets for JWSTand select the very best ones – that is how we get the most out of both missions,” explains Ehrenreich.

The mission extension also opens up opportunities for new, innovative observational methods. CHEOPS will continue to fulfil its core tasks while simultaneously serving as a laboratory in space to test new techniques, such as searching for moons around exoplanets or achieving even more precise determination of the exoplanets’ internal structure. “We hope this will give us a much more comprehensive picture of how planetary systems form, evolve, and how diverse they can be,” says Lendl.

Strengthening Switzerland as a hub for research and innovation

Through the efficient use of existing resources and close collaboration between universities, industry partners, and ESA, CHEOPS is sustainably strengthening Switzerland as a hub for research and technology. “High-precision technologies, software developments, and data analysis methods created as part of space missions are incorporated into other projects – from future space telescopes to applications outside the space sector, generating technological innovation while strengthening international scientific and industrial partnerships,” explains Fortier. “The renewed extension of the mission through 2029 underscores Switzerland’s leading role in exoplanet research. CHEOPS thus remains a cornerstone for the transition from exoplanet discovery to their detailed characterization,” Broeg concludes.

CHEOPS – in search of potential habitable planets

The CHEOPS mission (CHaracterising ExOPlanets Satellite) is an ESA “S-class missions” – small-class missions with an ESA budget much smaller than that of large- and medium-size missions, and a shorter timespan from project inception to launch.

CHEOPS is dedicated to characterizing the transits of exoplanets. It measures the changes in the brightness of a star when a planet passes in front of that star. This measured value allows the size of the planet to be derived, and for its density to be determined on the basis of existing data. This provides important information on these planets – for example, whether they are predominantly rocky, are composed of gases, or if they have deep oceans. This, in turn, is an important step in determining whether a planet has conditions that are hospitable to life.

CHEOPS was developed as part of a partnership between the European Space Agency (ESA) and Switzerland. Under the leadership of the University of Bern and ESA, a consortium of more than a hundred scientists and engineers from eleven European states was involved in constructing the satellite over five years.

CHEOPS began its journey into space on Wednesday, December 18, 2019 on board a Soyuz Fregat rocket from the European spaceport in Kourou, French Guiana. Since then, it has been orbiting the Earth on a polar orbit in roughly an hour and a half at an altitude of 700 kilometers following the terminator.

As a member state of the European Space Agency (ESA), Switzerland is participating in the CHEOPS telescope as part of the ESA Science Program and the PRODEX program (PROgramme de Développement d'EXpériences scientifiques). This program enables Swiss project teams from research and industry to participate in scientific missions through instruments they develop and build, and it funds these missions.This transfer of knowledge and technology between science and industry ultimately also gives Switzerland a structural competitive advantage as a business location – and enables technologies, processes and products to flow into other markets and thus generate added value for our economy.

More information: https://cheops.unibe.ch/

Bernese space exploration: With the world’s elite since the first moon landing

When the second man, "Buzz" Aldrin, stepped out of the lunar module on July 21, 1969, the first task he did was to set up the Bernese Solar Wind Composition experiment (SWC) also known as the “solar wind sail” by planting it in the ground of the moon, even before the American flag. This experiment, which was planned, built and the results analyzed by Prof. Dr. Johannes Geiss and his team from the Physics Institute of the University of Bern, was the first great highlight in the history of Bernese space exploration.

Ever since Bernese space exploration has been among the world’s elite, and the University of Bern has been participating in space missions of the major space organizations, such as ESA, NASA, and JAXA. With CHEOPS the University of Bern shares responsibility with ESA for a whole mission. In addition, Bernese researchers are among the world leaders when it comes to models and simulations of the formation and development of planets.

The successful work of the Department of Space Research and Planetary Sciences (WP) from the Physics Institute of the University of Bern was consolidated by the foundation of a university competence center, the Center for Space and Habitability (CSH). The Swiss National Fund also awarded the University of Bern the National Center of Competence in Research (NCCR) PlanetS, which it managed together with the University of Geneva from 2014 to 2026. The newly established Swiss Institute for Planetary Sciences (SIPS) is set to replace the NFS PlanetS. The universities of Bern, Geneva, and Zurich, as well as ETH Zurich, are once again involved in the initiative.

Exoplanet research in Geneva: 30 years of expertise awarded a Nobel Prize

The first exoplanet around a Sun-like star was discovered in 1995 by two researchers from the University of Geneva, Michel Mayor and Didier Queloz, laureates of the 2019 Nobel Prize in Physics. This discovery allowed the Department of Astronomy of the University of Geneva to be at the forefront of research in the field, with the construction and installation of HARPS at the ESO 3.6m telescope in La Silla in 2003. For two decades, this spectrograph was the most efficient in the world for determining the mass of exoplanets. However, HARPS was surpassed in 2018 by ESPRESSO, another spectrograph built in Geneva and installed at the Very Large Telescope (VLT) in Paranal, Chile.

Switzerland has also been involved in space-based observations of exoplanets with the CHEOPS mission, the result of two national expertises: the space know-how of the University of Bern in collaboration with its Geneva counterpart, and the ground-based experience of the University of Geneva assisted by its colleague in the Swiss capital. These two scientific and technical skills have also made it possible to create the National Center of Competence in Research (NCCR) PlanetS which has been managed by the University of Bern with the University of Geneva from 2014 to 2026. The newly established Swiss Institute for Planetary Sciences (SIPS) is set to replace the NFS PlanetS. The universities of Bern, Geneva, and Zurich, as well as ETH Zurich, are once again involved in the initiative.

11.06.2026