Galactic disc

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/galactic-disc

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. What is the disc components?Thin disc (young stars, gas, dust), thick disc (older stars)
2. What is the dominant motion?Ordered rotation around the galactic center
3. Why do stars in a galactic disc move in circles?Because the disc is flat and stars have very little motion up and down, so they mainly travel around the galaxy’s center in circular orbits.
4. How do spiral arms form in a galactic disc?Spiral arms are bright, dense regions where gas gathers and new stars form, but scientists are still figuring out exactly how they appear.

Velocity Dispersion: A measure of the random motions of stars within a galactic component.
Metallicity: The abundance of elements heavier than hydrogen and helium in a celestial object.
Protoplanetary Disc: A rotating disk of dense gas and dust surrounding a newly formed star, from which planets form.