# Does a red giant star produce more stellar wind than a yellow star?

Do red giant stars produce more stellar wind than when they were ordinary yellow stars? If so, how big a difference are we talking about?

• Yes. Many orders of magnitude more. Nov 3, 2021 at 17:46
• @constantthin What do you think? What research have you done to answer your own question? Nov 3, 2021 at 18:43
• The close vote for "This question currently includes multiple questions in one" doesn't make sense to me.
– uhoh
Nov 6, 2021 at 22:51

The Sun's current mass loss rate - a combination of the solar wind and radiation from the Sun - amounts to something like $$10^{-13}$$ solar masses per year.
The mass loss rates from red giant stars are variable, but much larger, and dominated by wind losses, rather than radiation. A common parameterisation of the average mass loss rate is the Reimers mass-loss rate (or variants thereof, e.g. Schroeder & Cuntz 2005) $$\dot{M} = -\eta \frac{L R}{M}\ (M_\odot /{\rm year})$$ where $$L$$, $$R$$ and $$M$$ are the luminosity, radius and mass of the red giant in solar units and $$\eta$$ is a fitting parameter that must be determined empirically and is about $$4\times 10^{-13}$$ in this unit system.
For a typical red giant with $$M=2M_\odot$$, $$L=1000 L_\odot$$ and $$R=100R_\odot$$, the Reimers formula gives $$2\times 10^{-8}$$ solar masses per year. However, for the very biggest giants and during pulsational mass loss during the AGB phase, mass loss rates could reach $$10^{-6}$$ solar masses per year or more.