Chemical signatures of iron predict red supergiant temperature

Red supergiants are a class of star that end their lives in supernova explosions. Their lifecycles are not fully understood, partly due to difficulties in measuring their temperatures. For the first time, astronomers have developed an accurate method to determine the surface temperatures of red supergiants.

source https://phys.org/news/2021-03-chemical-signatures-iron-red-supergiant.html