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Mission 8 of 16

Galaxies & the Universe

📋 What it is

A galaxy is a gravity-bound collection of billions of stars; the universe holds billions of galaxies.

🗣️ Coach says

Stars gather into galaxies — vast spirals or blobs of billions of stars bound by gravity, often around a central giant black hole. Our Milky Way is one galaxy among hundreds of billions in the observable universe.

🧠 Memory hook

Stars → galaxies → universe. We live in one galaxy: the Milky Way.

😂 Giggle

What did the Moon say to Earth?
"I'm always revolving around you — you really have a pull on me!"

😲 Whoa!

There are more stars in the observable universe than grains of sand on all of Earth’s beaches combined.

✅ Quick check: What galaxy do we live in, and what is a galaxy?

Say your answer out loud first — then reveal.

🧪 Try it! (2 minutes)

Sprinkle salt in a loose spiral on dark paper — a mini galaxy; each grain = billions of stars.

⭐ Do the round to earn your star →
🤸 Brain break: Spiral-arms: sweep both arms into a slow spiral around you.