image Science Objectives image Science Objectives image Science Objectives

Science objectives

Stellar formation, evolution and ISM: During the formation and throughout the entire life of stars and planets, a few key basic astrophysical processes, in particular magnetic fields, winds, rotation, and binarity, directly affect the internal structure of stars, their dynamics, and immediate circumstellar environment. They consequently drive stellar evolution, but also fundamentally impact the formation, environments, and fate of planets. We propose to follow the cycle of matter, from the ISM to the edges of the stellar systems, and, therefore, to study the formation, evolution, and 3D dynamical environments of all types of stars, and their role on the formation and evolution of planets and life. The enabling technique is high-resolution spectropolarimetry in both the UV and Visible domains.
Stellar radiation, magnetism and exoplanets: Arago will provide crucial constraints to characterise star-planet interactions and space weather along stellar evolution. It will probe the extended atmospheres of exoplanets, their evaporation and erosion, and allow interpretation of biomarkers by providing stellar UV irradiation properties. Arago will also provide key information on exoplanetary magnetic fields, thanks to the characterisation of stellar magnetic fields and bow shocks, and investigate the chemical composition of exoplanets, through their remnants around white dwarfs. This will allow us to constrain the environmental conditions for the emergence of life and help to understand the solar system, by putting it in the context of other stellar systems.
Additional science: In addition to its main science goals, Arago will also be able to tackle additional science topics. For example, Arago will be useful to study atomic and molecular physics, ultra-cool dwarfs and brown dwarfs, or solar system objects.