Pre-main-sequence 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/pre-main-sequence-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. What is the scientific classification?Pre-main-sequence star (PMS object)
2. What is the energy generation mechanism?Primarily gravitational contraction, converting potential energy to thermal energy
3. What is a pre‑main‑sequence star?It is a baby star that has finished gathering most of its mass but hasn't started hydrogen fusion yet. It shines by contracting and getting hotter inside.
4. Why do pre‑main‑sequence stars have big disks around them?The disks are leftover gas and dust from the star’s birth, and they are where planets can form.

Protostar: The initial stage of stellar evolution characterized by accretion from a surrounding envelope.
Gravitational Contraction: The process by which a celestial body shrinks under its own gravity, releasing energy.
Hertzsprung-Russell Diagram: A scatter plot of stars showing the relationship between their luminosity and surface temperature.
Hayashi Track: The evolutionary path of low-mass pre-main-sequence stars on the H-R diagram during the radiative phase.