Lesson 10 of 10 · Space
Experiment⭐ 30 XP🚀 StarbaseDetecting Planets Around Other Stars
Detecting Planets Around Other Stars.
🎯 Your mission
Predict it first. Then prove yourself right (or wrong).
⚡ The twist
The light you see now started its trip a long time ago.
Mind = Blown
🌌 If you could drive a car straight up at highway speed, you'd reach space in under an hour.
Make a hypothesis first
Guess: how big does that look from here vs. from there?
What You'll Learn
Most exoplanets are found by the transit method: a planet crossing its star dims it very slightly, on a repeating schedule. The depth of the dip gives the planet's size and the interval gives its year.
Key Words
Tap a word to see its definition.
Materials Needed
- lamp
- light sensor or phone lux app
- balls of two sizes
- dark room
Safety First
- The lamp gets hot — let it cool before moving it, and keep its cable clear of the walkway.
Steps
Read the explanation above and note the two key terms before you start.
Model a transit by moving a small ball across a lamp while a light sensor records brightness. Plot the light curve, then repeat with a larger ball and compare the depth of the dip.
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 2In the transit method, a larger planet produces a dip that is:
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?”
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Detecting Planets Around Other Stars
Predict it first. Then prove yourself right (or wrong).
Full screen — no distractions
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