How To Use The Hertzsprung-Russel Diagram?


I’m supposed to explain a project about this and I have no idea how to use it.

In: Physics

It’s a visualization of different star types. It groups them based on temperature and brightness. Top left is hot and bright, bottom left is hot and dim, top right is cool and bright, and bottom right is cool and dim. Most stars fall along the Main Sequence in the center.

The main thing that Hertzsprung-Russel diagram did was that it demonstrated the relationship between temperature and luminosity (“brightness”) in stars, thus providing evidence for/about stellar evolution. Specifically, most stars will increase in magnitude and temperature over their lifetimes until they reach a “turning point”, after which they will hold steady in luminosity but decrease in temperature (this is because they’re expanding to become giants or supergiants).

These days, the Hertzsprung-Russel diagram is primarily used to estimate the distance to stars, by translating their temperature (obtained from looking at their color spectrum) into an absolute magnitude (how bright they *should* be) and comparing that against their apparent magnitude (how bright they *are*).