Physics · KS3 Y9 · Space & Gravity

Galaxies and the universe

Galaxies and the universeFree10:56Heddy Score 3 of 7, below the standard
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What you need to know

  • Astronomical distances grow from hundreds of thousands of kilometres within the Earth–Moon system to millions of light-years between galaxies.
  • An astronomical unit is useful for distances within the Solar System; a light-year is useful between stars.
  • The Milky Way is one galaxy among many, and the observable universe spans an enormous region of space.

In this clip

Runs 10:56, from 0:04 to 11:00 of the full video.

Also coversThe light year
Heddy Score3/7, Below the standard
See the seven stars
  • Trusted source · passed. The creator's own upload, live and playable here.
  • On the map · not judged yet. A teacher watched it: it mainly teaches this map topic.
  • Spec-true · not judged yet. Accurate, and right for the current UK specification.
  • Focused · passed. One idea, short enough to watch in one go.
  • Accessible · passed. Good captions, clear sound and pictures.
  • Safe for children · not judged yet. Right for 11 to 16 year olds, with no sales pitch.
  • Proven · not judged yet. Earned from our students: they learn from it, find it helpful and watch it to the end.
★ passed · ☆ pending · ✕ failed
Our students

Not enough students yet

Our own students' answers. These are what move ★7 Proven.
On YouTube

15.5M views · 169K likes · Science Time 1.17M subscribers

As reported by YouTube on 2026-11-02. Not part of the Heddy Score.
How the Heddy Score works

Why we picked it

Uses a scale-by-scale journey to make the size of the universe easier to picture.

Science Time on YouTubechecked 2026-10-20

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