Observational constraints for solar-type Stellar winds

Ionized winds from late-type main-sequence stars are important for stellar spin-down and therefore the evolution of stellar activity; winds blow an "astrosphere" into the interstellar medium that absorbs a large part of galactic cosmic rays; and the winds play a key role in shaping planetary environments, in particular their upper atmospheres. These issues have been well studied for the solar wind but little is known about winds escaping from other solar-type stars. Several methods have been devised to either detect winds directly or to infer the presence of such winds from features that are shaped by the winds. This paper summarizes these methods and discusses exemplary findings. There is need for more studies using multiple methods for the same stars.