CurriculumGrade 12Science

The Universe and Its Stars

Aligned to HS-ESS1 — Next Generation Science Standards.

What this lesson teaches

The universe began with the Big Bang and has expanded ever since. Stars form, fuse elements, and die, recycling matter into new stars and planets.

Worked example

Our sun fuses hydrogen into helium, releasing energy; when massive stars die, they scatter heavier elements that form planets like Earth.

Practice questions

  1. What evidence supports the Big Bang?
  2. How do stars produce energy?
  3. Where did the heavy elements in Earth come from?

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Every lesson comes with a video taught in English and Spanish — the same video the QR code in the printed workbook opens.

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En español

El universo y sus estrellas

El universo comenzó con el Big Bang y se ha expandido desde entonces. Las estrellas se forman, fusionan elementos y mueren, reciclando materia en nuevas estrellas y planetas.

Ejemplo: Nuestro sol fusiona hidrógeno en helio y libera energía; cuando las estrellas masivas mueren, dispersan elementos más pesados que forman planetas como la Tierra.

More Earth & Space Science lessons

Earth's Climate SystemsHS-ESS2Human Sustainability and ResourcesHS-ESS3

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