91福利

Professor Moira Jordine

(School of Physics & Astronomy University of St Andrews)

Title: Star spots and flares: living with a delinquent star

Abstract:

Stars can be both friend and foe for life that is trying to evolve on a planet. They provide essential light and warmth, without which life finds it hard to exist at all, but a star's magnetic activity can also be damaging. This magnetic activity comes in the form of a stellar wind that may strip away a planet's atmosphere and also in the form of flares. These are enormous releases of energy from the star's corona that not only increase the star's X-ray emission but can also throw massive clouds of hot gas towards a planet. When life was evolving on Earth, the Sun was younger and more active, with a stronger wind and more powerful flares, but even today, both satellite electronics and power grids on Earth may be damaged in a solar flare. So what makes a star a good neighbour? In this talk I will describe our current understanding of the magnetic activity of other stars and show how we are assessing the impact this may have on any orbiting planets.