ciarenni t1_j9wf6oh wrote on February 25, 2023 at 1:14 AM

Reply to comment by Brickleberried in Massive 'forbidden planet' orbits a strangely tiny star only 4 times its size. by Rifletree

Yeah, it wasn't the best example star but my point was that just because it's small doesn't mean anything about how much mass it has, which is the point that I feel like the headline was missing.

Brickleberried t1_j9zisc7 wrote on February 25, 2023 at 6:42 PM

Radius of a main sequence star is proportional to the mass of the star. If you know the radius, you can pretty accurately get the mass. (It depends some on age and metallicity too, but not that much, as long as it hasn't evolved to a red giant yet.)

Planets, on the other hand, don't follow the rule nearly as well, especially for gas giants. Jupiter and a brown dwarf 80x the mass of Jupiter both have the same radius.