This definitions covers Key Terms within Life Cycle of Stars for GCSE Physics. Revise Life Cycle of Stars in Space Physics for GCSE Physics with 13 exam-style questions and 12 flashcards. This topic appears regularly enough that it should still be part of a steady revision cycle. It is section 7 of 14 in this topic. Make sure you can use the exact wording confidently, because definition marks are often lost through vague language.
📖 Key Terms
- Nebula
- A large cloud of gas (mainly hydrogen) and dust in space. The starting point for star formation.
- Protostar
- A collapsing, heating cloud of gas that will become a star once the core temperature is high enough for nuclear fusion to begin.
- Main sequence star
- A stable star where hydrogen fuses into helium in the core. Radiation pressure from fusion balances gravity. Stars spend most of their lives in this phase.
- Red giant / Red supergiant
- An expanded, cooler star formed when a main sequence star runs out of core hydrogen. Red giants come from sun-like stars; red supergiants from massive stars.
- Planetary nebula
- The shell of gas expelled from a red giant as its outer layers are blown off. Named for appearance, not connected to planets.
- White dwarf
- The dense, Earth-sized remnant of a sun-like star's core after the planetary nebula phase. Made of carbon and oxygen, no longer fusing.
- Supernova
- A catastrophic explosion of a massive star when its iron core collapses. Briefly outshines an entire galaxy and creates all elements heavier than iron.
- Neutron star
- The extremely dense remnant after a supernova when the core has 1.4 to 3 solar masses. Made of neutrons; a teaspoon weighs about a billion tonnes.
- Black hole
- The remnant of a supernova when the core mass exceeds about 3 solar masses. Gravity so strong nothing — not even light — can escape.
Practice questions for Life Cycle of Stars
The light from a distant galaxy is red-shifted. What does this tell us about the galaxy?
Explain what red-shift is and what it tells us about a distant galaxy.
Quick recall flashcards
What is a nebula?
A cloud of gas and dust where gravity pulls material together to form new stars
What is a protostar?
Material that heats up as it collapses from a nebula, but is not yet fusing hydrogen