How do you estimate/calculate how much solar wind a star produces? (Can we even make a passable attempt?) I'm trying to work out whether a fictional exoplanet in orbit around R Coronae Borealis would need a magnetic field (as there appears to now be some debate on a cursory google search on how much effect one has), and if so, whether it would need to be stronger or weaker than Earth's. (The planet is orbiting at a distance of roughly 104AU.) I sort of assume that solar wind would have the same reduction in effect as the stellar flux over distance... But I have no idea whether that's true or not, or what we know (if anything) of the theorhetical stellar wind an RCB yellow supergiant might produce; whether it would be considerably more (if in proportion to the stellar flux, for example, it would be about 80ish% more than Earth's at that distance... presumably requiring a proportionally stronger magnetic field) or less or whether it's just a function of output verses distance or whether the type of star also has an effect. Can anyone throw any light on the subject for me, please?