Cepheid stars vary in their brightness (growing bright then dim) according to their mass. So, the idea is, if you know the brightness (period), you know the mass. This helps you look at how bright the star looks (apparent magnitude), knowing how bright it should be according to its mass, and figure out how far away the star is. Knowing how far away the star is, tells you how big the galaxy is.

James's profile picture
James Vardini
·

null students helped

·

2 years ago


Similar questions in Science

Maths

Asked by Bhairavi

Inequalities

English

Asked by Cristina

What is a feminine rhyme?

English

Asked by Cristina

What is a masculine rhyme?

French

Asked by Wenli

This is my questions for you

Tutors who could help with undefined

Tutors who could help with undefined