Surrey Satellite Technology has been selected by the European Space Agency (ESA) for the competitive design phase of CHEOPS science satellite, which will improve mankind's understanding of exoplanets - planets orbiting distant stars outside our solar system. The contractor selection for the implementation phase is planned by mid-2014 and the launch is scheduled late 2017.

The CHaracterising ExOPlanets Satellite (CHEOPS) will finely characterise known exoplanets and their parent stars with an unprecedented accuracy. The satellite will measure the orbit and radius of those exoplanets, enabling the scientists to assess their potential habitability.

The mission will also act as a "scout" performing preliminary observations on targets for the future European Extremely Large Telescope and James Webb Space Telescope that will be capable of more detailed analysis.

CHEOPS was selected from 25 missions proposed in response to ESA Call for Small Missions in 2012, which was targeting innovative small science missions that offer high value at low cost.

CHEOPS is jointly developed by ESA and a consortium of Member States led by Switzerland: The Swiss-built instrument using a Ritchey-Chretien optical telescope will observe the stars and their orbiting planets, while ESA is responsible for the provision of the satellite platform and the launch.

Over the next 10 months SSTL will design the satellite platform, which will host the telescope payload. To provide the mission within a short schedule and at low cost, ESA asked that any solution be based on an existing, flight-proven, satellite platform.

SSTL's solution is based on a variant of the highly successful SSTL-150 platform, which has seen recent service in Canada's Sapphire space surveillance mission and the 5-satellite RapidEye Earth observation constellation.

In awarding the contract to SSTL, Frederic Safa, Head of Future Missions Office in ESA's Science and Robotic Exploration Directorate stated: "We chose SSTL for this study for a combination of reasons such as their proven ability to build reliable low-cost missions and their past experience with satellites carrying high-performance optical telescopes."

SSTL's Head of Science, Doug Liddle, commented: "We are delighted that ESA selected SSTL to design the CHEOPS mission. We will draw on our experience to design a low cost, but high value solution that will demonstrate that ambitious science missions can be launched both quickly and economically."

CHEOPS is envisaged as the first in a series of missions in the ESA Science Programme that will utilise small satellites for low cost and rapid development, in order to offer greater flexibility in response to new ideas from the scientific community and complement to the larger missions of ESA's Science Programme.