Lesson 3 of 6 · Spacetime
Lesson⭐ 30 XP🚀 StarbaseThe Life Cycle of Stars
Spacetime.
🎯 Your mission
Master the concept. Use it tomorrow.
⚡ 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
Stars form when gravity collapses a nebula until fusion ignites. A star like the Sun spends billions of years on the main sequence, swells into a red giant, then sheds its layers to leave a white dwarf. Much heavier stars end as supernovae, leaving neutron stars or black holes.
Key Words
Tap a word to see its definition.
Steps
Read the explanation above and note the two key terms before you start.
Draw two parallel flowcharts, one for a Sun-mass star and one for a star twenty times heavier, labelling every stage and the force balance that ends it. Mark where the elements in your own body were made.
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 2A star spends most of its life:
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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The Life Cycle of Stars
Master the concept. Use it tomorrow.
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