Lesson 2 of 6 · Spacetime
Experiment⭐ 30 XP🚀 StarbaseOrbits Are Continuous Free Fall
Spacetime.
🎯 Your mission
Run the experiment. Find out what really happens.
⚡ The twist
Gravity is invisible — but it shapes everything.
Mind = Blown
🌟 The light from the closest star (after the sun) takes 4 years to reach you.
Make a hypothesis first
Before you check: which is closer?
What You'll Learn
A satellite in orbit is falling all the time; it simply moves sideways fast enough that it keeps missing the Earth. Astronauts float not because gravity is absent — at the space station it is about 90% of its surface value — but because they fall with their craft.
Key Words
Tap a word to see its definition.
Materials Needed
- strong bucket with handle
- water
- large open outdoor space
Safety First
- Outdoors only, well away from people and windows.
- Check the handle and its fixing before every swing.
Steps
Read the explanation above and note the two key terms before you start.
Swing a bucket of water in a vertical circle fast enough that none spills, then slow it until it does. Relate the critical speed to the point where gravity alone can no longer supply the centripetal force.
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 2Astronauts on the space station float because they are:
Where you see this in real life
Every sunrise and every shadow is this idea in action.
Stretch Challenge
Try this in real life this week.
Look at the moon tonight. Notice its shape. Look again in 3 days.
For the dinner table
“If you could visit any planet, which would you pick and why?”
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Send it to a parent who's looking for a 10-minute kitchen science win.
Ready?
Orbits Are Continuous Free Fall
Run the experiment. Find out what really happens.
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