Abstract
The current solar wind is well studied from remote observations and in situ measurements. However, we have very little information of the solar wind as it has evolved. We investigate the evolution of the solar wind by modeling the winds of solar analogues. By using X-ray temperatures as proxies for wind temperatures, we find that a break in behaviour occurs. At 2 Gyr there is a sharp decline in coronal temperatures, which results in a steep decay in mass loss rates for older stars. As the wind is responsible for stellar spin down, through angular momentum loss due to magnetised winds, our results suggest a decline in angular momentum loss for older stars. This agrees with recent observations which find anomalously high rotation rates in older stars. We also find that this evolution in the wind has adverse effects on the Earth’s magnetosphere, with an Earth aged 100 Myr having a magnetosphere 3 Earth radii in size.
Dúalta Ó Fionnagáin
Data Scientist in Climate Change, Remote Sensing, Machine Learning
Data Scientist focused on climate change adaptation using Earth observation