Dark matter

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/dark-matter

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 Dark matter?Dark matter comprises roughly 26.8% of the universe's total mass-energy density
2. What is the primary interaction mechanism?Gravitational interaction is the dominant observed effect; non-electromagnetic
3. What is the dominant cosmological model?Cold Dark Matter (CDM) scenario is favored for explaining structure formation
4. Why do scientists think there is dark matter in galaxies?Stars in the outer parts of galaxies move faster than expected from visible stars alone, so extra invisible mass must be there to keep them moving.
5. How do we know dark matter exists from the Bullet Cluster?In the Bullet Cluster, the hot gas we can see is separated from the center of gravity that bends light, showing that most mass is invisible dark matter.

Lambda-CDM Model: The standard model of cosmology, describing the universe's composition and evolution.
Gravitational Lensing: The bending of light by gravity, acting like a cosmic magnifying glass.
Cosmic Microwave Background (CMB): The faint afterglow radiation from the Big Bang, providing a snapshot of the early universe.
Baryonic Acoustic Oscillations (BAO): Imprints in the distribution of matter from sound waves in the early universe, used to measure cosmic distances.