Lesson 7 of 10 · Space
Experiment⭐ 30 XP🚀 StarbaseHow We Know What Stars Are Made Of
How We Know What Stars Are Made Of.
🎯 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
Each element absorbs light at its own set of wavelengths, leaving dark lines in a star's spectrum. Matching those lines against laboratory samples tells us a star's composition without going anywhere near it.
Key Words
Tap a word to see its definition.
Materials Needed
- diffraction grating
- filament lamp
- gas discharge tubes
- dark room
Safety First
- Discharge tubes use high voltage — a teacher must set up and operate them.
- Never look directly at a bright filament for more than a moment.
Steps
Read the explanation above and note the two key terms before you start.
View several light sources through a diffraction grating and sketch each spectrum. Compare a filament lamp's continuous band with a gas discharge tube's separate lines and explain what the difference reveals.
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 2Dark lines in a star's spectrum are caused by elements that:
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?”
Next Smart Experiment
We'll pick an experiment that matches exactly how you're thinking right now.
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Send it to a parent who's looking for a 10-minute kitchen science win.
Ready?
How We Know What Stars Are Made Of
Predict it first. Then prove yourself right (or wrong).
Full screen — no distractions
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