Redshift

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/redshift

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 primary redshift mechanisms?Doppler (relative motion), gravitational (escaping gravity), and cosmological (spacetime expansion)
2. What is the redshift parameter 'z'?Quantifies the fractional change in wavelength (positive for redshift, negative for blueshift)
3. Why does light from faraway stars look redder?Light from stars that are moving away from us or escaping strong gravity gets stretched, so its color shifts toward red. When stars move toward us, the light shifts toward blue instead.
4. How does the universe's expansion cause redshift?As the universe expands, the space between galaxies stretches, and the light traveling through that space gets stretched too. This makes the light’s wavelength longer, which we see as redshift.

Electromagnetic Spectrum: The range of all types of electromagnetic radiation, ordered by frequency and wavelength.
Spectroscopy: The study of the interaction between matter and electromagnetic radiation, analyzing light's spectrum.
General Relativity: Einstein's theory describing gravity as the curvature of spacetime caused by mass and energy.