The Difference between hot star and cold star | Colour of stars

Astronomy, our galaxy, the planets, and the stars are all topics that have always fascinated me. It is very amazing to learn about the universe and the different things that exist outside of the earth’s atmosphere. Therefore, in this article, I am going to talk about one interesting thing about the outer world, and that is the difference between a hot star and a cold star, and for that, we will discuss the COLOUR OF STARS.

Colours of Stars Poster Created by Rutik Patel (me)

This article includes :

1. Colours of Stars
2. Blue Star
3. Red Star
4. Yellow Star
5. Summary

Colours of Stars

The universe is stunning; it is filled with different types of stars and planets. Some of them differ in size, some in appearance, and some in colour.

Yellow, blue, red, orange, and white are the five most common colours of stars. One of them The bluest stars are the warmest, while the reddest stars are the coldest. Their colours are based on the star’s temperature.

Let’s take a quick look at stars and colours with the help of the following illustration:

Image source : https://sciencenotes.org/

Blue Stars

If we talk about the hottest stars, then they are blue, and their temperatures are approximately 20000 K to 25000 K. Perhaps the figure will rise in the future. It is four times higher than the temperature of the sun.

Examples of Blue Star :

1. Bellatrix ( 22,000 K )
2. Spica ( 22,400 K )

Illustration Created by Rutik Patel (me)

Red Star

Now we’ll look at the coldest stars, which are highlighted in red and have average temperatures of 3000 K. It is very much lower than the temperature of the sun. Currently the coldest star is CFBDSIR 1458+10B, with a temperature of approximately 370 K.

Examples of the Red Star :

1. Betelgeuse ( 3500 K )
2. Antares ( 3500 K )

Illustration Created by Rutik Patel (me)

Yellow Star

Yellow Star has a medium temperature between cold and hot. The best example of a yellow star is none other than the Sun. The surface temperature of the sun is 6000 K.

Illustration Created by Rutik Patel (me)

Summary :

Various colours in the stars indicate different temperatures. The hottest stars tend to appear blue or blue-white, whereas the coolest stars are red. A colour index of a star is the difference in magnitudes measured at any two wavelengths and is one way that astronomers measure and express the temperature of stars.