O-type star

High school (ages 12+)
Space & Astronomy

Name:

Date:

Step 1 · Read the article

Open the article and read it at the level above. Then answer the questions below in your own words.

https://smallwhale.org/articles/o-type-star

Write what each word means, using the article.

Do not copy the article. Write two things you learned, the way you would explain them to a friend.

Answers below are taken from the article’s stored facts, so they match what the student read.

1. How heavy is O-type star?15 to 90 M☉ (Solar Masses)
2. What is the spectral type?O
3. What is the effective surface temperature?20,000 K to 30,000+ K
4. What makes O-type stars so hot and bright?They have surface temperatures above 20,000 K and masses 15–90 times the Sun, so their cores fuse hydrogen very quickly, producing huge ultraviolet light and making them millions of times brighter than the Sun.
5. Why do O-type stars have such short lifetimes?Their huge mass and intense fusion burn hydrogen very fast, so they use up their fuel in only a few million years, much shorter than the Sun’s life.

Hertzsprung-Russell Diagram: A scatter plot of stars showing the relationship between their luminosity and temperature.
Spectral Lines: Dark or bright lines in a star's spectrum caused by the absorption or emission of light by atoms.
Ionization: The process of an atom or molecule losing or gaining electrons, becoming an ion.
Galactic Chemical Evolution: The process by which the abundance of chemical elements in a galaxy changes over time.