Extreme solar events

TL;DR

This paper reviews the evolution of research on extreme solar and solar-terrestrial events, analyzing historical and modern data to understand rare, impactful phenomena like superflares and geomagnetic storms.

Contribution

It compiles a comprehensive dataset of 100- and 1000-year event occurrences and discusses the physics of extreme solar phenomena beyond typical large events.

Findings

Compiled a table of long-term occurrence frequencies for space weather events.

Analyzed the Sun-like nature of superflare stars and their relation to extreme solar events.

Discussed the potential for unpredictable 'black swan' and 'dragon king' solar phenomena.

Abstract

We trace the evolution of research on extreme solar and solar-terrestrial events from the 1859 Carrington event to the rapid development of the last twenty years. Our focus is on the largest observed/inferred/theoretical cases of sunspot groups, flares on the Sun and Sun-like stars, coronal mass ejections, solar proton events, and geomagnetic storms. The reviewed studies are based on modern observations, historical or long-term data including the auroral and cosmogenic radionuclide record, and Kepler observations of Sun-like stars. We compile a table of 100- and 1000-year events based on occurrence frequency distributions for the space weather phenomena listed above. Questions considered include the Sun-like nature of superflare stars and the existence of impactful but unpredictable solar "black swans" and extreme "dragon king" solar phenomena that can involve different physics from that operating in events which are merely large.