Distant object color indices

Have you ever looked at a rainbow and noticed that it has different colors like red, orange, yellow, green, blue, and purple? Scientists have a way of measuring the colors of things called color indices.

Now imagine that you are looking up at the sky and you see a very far away star. This star might look white to you because it is so far away. But scientists want to know more about the star, so they use special machines to measure the colors of the light that the star gives off.

They measure the amount of red, green, and blue in the light and use this information to create a number called a color index. This number can tell scientists about the temperature of the star, how much light it gives off, and what kinds of gases are in the star. It's like a secret code that helps the scientists learn more about the star, even though it's very far away.