As part of its Cosmic Vision program, the European Space Agency has validated the ARIEL mission, which will begin in 2028. Devoted to the study of the atmosphere of the worlds outside the solar system, it is part of a series of European projects devoted to exoplanets.
If NASA is at the forefront of the discovery and study of other worlds outside the solar system, thanks in part to the tremendous work done by the Kepler Space Telescope, the US agency is not the only one to mobilize in this area. The Old Continent is also getting involved with a number of missions that will be deployed between 2018 and 2028.
By the end of the year, the CHEOPS (CHaracterising ExOPlanets Satellite) mission must be launched to measure exoplanet transits by deploying a small photometric observatory in low orbit. Later, in 2026, ESA also plans to launch a mission dubbed PLATO (PLAnetary Transits and Oscillations of Stars) to study planetary transits and stellar oscillations.
But that’s not all: the European Space Agency is also counting on the upcoming ARIEL (Atmospheric Remote Sensing Infrared Exoplanet Large-survey) mission, which will begin in 2028 and last four years. This project was approved by ESA on Tuesday March 20th as part of its global Cosmic Vision program, which is used to define future missions for the 2015-2025 period.
“ARIEL will address fundamental issues about the composition of exoplanets and how planetary systems are formed and evolve, by studying the atmospheres of hundreds of planets orbiting different types of stars, which will make it possible to evaluate the diversity of properties of individual planets as well as within certain populations of worlds,” writes ESA.
ARIEL will measure the chemical footprints of the planets’ atmospheres when they pass in front of their host star. This method is known as the transit method, which measures brightness variations to a high degree of accuracy. ARIEL will also conduct more detailed study on some handpicked worlds, observing their cloud cover and seasonal and daily atmospheric variations.
Despite the incredible distance separating ARIEL from its observation subjects, the space telescope will be able to detect water vapor, carbon dioxide, methane and more exotic metallic compounds, taking into account the chemical environment of the host star. ARIEL will also focus on hot worlds, that is to say those relatively close to their star.