By Prof. Roger Maurice BONNET, astrophysicist, emeritus director of research at the CNRS (Institute of Astrophysics of Paris), scientific director at ESA from 1983 to 2001, executive director of the International Space Science Institute in Berne (Switzerland) from 2003 to 2013, member of the Royal Swedish Academy of Sciences, honorary member of the Academy.
The Sun, our star, offers the right conditions for the emergence of life on Earth. According to current models, its radiation warms up regularly at the rate of 1% per million years, offering humanity a life expectancy of about 1.5 billion years. However, other natural and anthropogenic factors may shorten this time. Continuous monitoring of our star is therefore a necessity in view of climate change and the prediction of phenomena related to its magnetic activity in particular. For this purpose, the role of satellites is irreplaceable: they offer a unique tool whose power and effects will be developed and discussed during the presentation.