The satellite will be launched from the Guiana Space Center, Europe’s spaceport in Kourou, French Guiana, between late 2018 and early 2019 using a Soyuz launch vehicle.

CHEOPS will target nearby, bright stars already known to have planets orbiting around them. Through high-precision monitoring of a star’s brightness, scientists will examine the transit of a planet as it passes briefly across the star’s face. In turn, this will allow an accurate measurement of the planet’s radius. For those planets with a known mass, the density will be revealed, providing an indication of the internal structure.

These key parameters will help scientists to understand the formation of planets from a few times the mass of the Earth (known as “super-Earths”) up to Neptune-sized worlds. The data also will help refine ideas about how planets change orbits during the formation and evolution of their parent systems.

CHEOPS is an ESA mission implemented in partnership with Switzerland and a number of other Member States.

Based on an Airbus Defence and Space satellite platform, CHEOPS will weigh about 300 kg. at launch, and will be injected into a 700-km.-altitude Sun-synchronous dawn-to-dusk orbit around Earth, inclined by approximately 98º to the Equator as it circles the globe from pole to pole.

Following the signing of this contract, Stéphane Israël, Arianespace’s Chief Executive Officer, said: “We are very proud to serve once again major European space programs with this scientific mission, allowing science to progress in its quest for understanding the formation and evolution of planets orbiting other stars. Many thanks to the European Space Agency for its renewed confidence. This contract is a true recognition of the reliability and diversity of launch service solutions offered by Arianespace.”

About Arianespace

Arianespace uses space to make life better on Earth by providing launch services for all types of satellites into all orbits. It has orbited more than 550 satellites since 1980, using its family of three launchers, Ariane, Soyuz and Vega, from launch sites in French Guiana (South America) and Baikonur, Kazakhstan. Arianespace is headquartered in Evry, near Paris, and has a technical facility at the Guiana Space Center, Europe’s Spaceport in French Guiana, plus local offices in Washington, D.C., Tokyo and Singapore. Arianespace is a subsidiary of ArianeGroup, which holds 74% of its share capital, with the balance held by 17 other shareholders from the European launcher industry.