The European Space Agency has announced that the Atmospheric remote-sensing infrared exoplanet large-survey (Ariel) mission has moved from the study phase to the implementation phase. An industrial contractor will be selected to build the spacecraft. Ariel’s mission is to study what exoplanets are made of and how they form and evolve.
To do this, the mission will survey a diverse sample of around 1000 planetary atmospheres simultaneously in visible and infrared wavelengths. It will be the first mission dedicated to measuring the chemical composition and thermal structures of exoplanets. The mission will investigate how planet chemistry is linked to the environment in which it formed.
The ESA also hopes to determine with the mission whether the type of star drives the physics and chemistry of planetary evolution. Observations made by the spacecraft will provide insight into the early stages of planetary and atmospheric formation along with their subsequent evolution. Scientists say studying these exoplanets will provide insights into how our solar system fits into the overall cosmos.
The ESA selected Ariel in 2018 as the fourth medium-class space mission in the ESA Cosmic Vision plan. The ESA adopted the mission during its Science Program Committee meeting on November 12, paving the way towards the construction of the spacecraft. Ariel will be the third dedicated exoplanet mission to launch within ten years.
Each of the missions will investigate a unique aspect of exoplanet science. In December 2019, the ESA launched Cheops, the CHaracterizing ExOPlanet Satellite. Plato, the PLAnetary Transits and Oscillations of stars mission launch in 2026. Ariel is planned to launch in 2029 and will focus on warm and hot planets, including super-Earths and gas giants that orbit close to parent stars. The ESA will invite industry to make bids to supply spacecraft hardware for the mission in the coming months, and by the summer of next year, a prime industrial contractor will be selected for the build.