Sirius

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/sirius

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 Sirius?Approximately 2.02 solar masses
2. What is the spectral classification?Sirius A: A1V; Sirius B: DA2 (white dwarf)
3. What is the orbital period?Approximately 50 years
4. What makes Sirius the brightest star we can see?Sirius is very close to Earth and very bright, so it looks huge in the sky. It is about 8.6 light‑years away and shines 25 times brighter than the Sun.
5. Why does Sirius look like a double star?Sirius is actually two stars, Sirius A and Sirius B, that orbit each other. Sirius A is a big, bright star and Sirius B is a small, faint white dwarf.

Main Sequence Star: A star that is in the longest stage of its life, fusing hydrogen into helium in its core.
White Dwarf: The dense, Earth-sized remnant core of a star that has exhausted its nuclear fuel, primarily composed of electron-degenerate matter.
Axial Precession: The slow, conical wobble of a planet's or star's rotational axis over long periods.
Proper Motion: The apparent angular motion of a star across the celestial sphere relative to the background stars.