stellar wind

Stellar wind is outward-moving gas from a stellar atmosphere, presumed steadier than distinct bursts. It is the analog of solar wind for other stars, but for other types of stars, the makeup and other characteristics of the wind can vary. For example, massive stars tend to have much stronger stellar wind, to the point of emitting much more of their mass over a much shorter lifetime. The term superwind refers to an extreme wind in a very late phase of an asymptotic giant branch (AGB) star.

A bubble within the interstellar medium (ISM) formed from the outgoing stellar-wind is termed an asterosphere (the Sun's is called the heliosphere), and for very strong stellar winds, a stellar-wind bubble.

Stellar wind rates vary:

• Solar wind: 250-750 km/s, mass loss: 10^-14 solar masses/year.
• Massive O-type star or B-type star, up to 2000 km/s, 10^-6 solar masses/year.
• Post-main-sequence star: ~10 km/s (slow, but proceeding from the large (giant) surface much further from the center), 10^-3 solar masses/year.