Lesson 4 of 6 · Spacetime
Experiment⭐ 30 XP🚀 StarbaseRedshift and the Expanding Universe
Spacetime.
🎯 Your mission
Set it up. Test it. Be amazed.
⚡ The twist
Up there, the rules of down here stop working.
Mind = Blown
🪐 A day on Venus is longer than a year on Venus.
Make a hypothesis first
Predict: what would happen on the moon vs. on Earth?
What You'll Learn
Light from distant galaxies is stretched to longer wavelengths, and the further away a galaxy is, the greater the shift. That relationship implies space itself is expanding, which is the strongest evidence for the Big Bang some 13.8 billion years ago.
Key Words
Tap a word to see its definition.
Materials Needed
- balloon
- marker pen
- flexible tape measure
Safety First
- Do not over-inflate; burst fragments are a choking hazard.
Steps
Read the explanation above and note the two key terms before you start.
Draw dots on a deflated balloon, measure the separations, inflate it and measure again. Show that every dot sees every other receding, and that the most distant dots recede fastest — a two-dimensional model of expanding space.
Record what actually happened, including anything that did not match what you expected.
Write a conclusion that answers the question this lesson opened with, and state your uncertainty.
Check Your Understanding
Question 1
1 of 2Light from a receding galaxy is shifted towards:
Where you see this in real life
GPS, weather forecasts, and the seasons all rely on this.
Stretch Challenge
Try this in real life this week.
Find a constellation in the sky. Look it up. Tell someone its story.
For the dinner table
“If you could visit any planet, which would you pick and why?”
Next Smart Experiment
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Send it to a parent who's looking for a 10-minute kitchen science win.
Ready?
Redshift and the Expanding Universe
Set it up. Test it. Be amazed.
Full screen — no distractions
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