Galaxy formation and evolution

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/galaxy-formation-and-evolution

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 initial seed mechanism?Galaxies are hypothesized to originate from quantum fluctuations amplified by cosmic inflation
2. What is a galaxy and how does it form?A galaxy is a huge city of stars, gas, and dark matter that starts from tiny bumps in the early universe. Those bumps grow into dark matter halos, and normal matter falls in, cools, and makes the first stars and galaxies.
3. Why do galaxies look different from each other?Galaxies change shape and size when they merge with other galaxies, when stars explode, and when they lose gas in crowded places. These events make some galaxies round, some flat, and some full of new stars.

Cosmic Inflation: A hypothetical period of exponential expansion of space in the very early universe, explaining its flatness and homogeneity.
Dark Matter Halos: Spherical distributions of dark matter that provide the gravitational scaffolding for galaxy formation.
Baryonic Matter: The 'normal' matter composed of protons and neutrons that makes up stars, planets, and gas.
Supermassive Black Holes: Gigantic black holes, millions to billions of times the mass of the Sun, found at the centers of most galaxies.