Chapter 02 of 5
Helium and the Triple-Alpha
How stars bridge the 'mass gap' to create carbon through rare, high-heat collisions.
- The Ash
Helium Accumulation
As hydrogen fuses, it creates helium 'ash' that settles in the star's core. This inert pile waits for even higher temperatures to ignite.
- Thermal Shift
Core Contraction
When hydrogen runs low, gravity compresses the core further. This increases the internal temperature to over 100 million Kelvin.
- The Mass Gap
The 5-Nucleon Problem
There is no stable atom with a mass of 5. Fusing a proton with helium creates an instant decay, blocking the path to heavier elements.
17 more cards in this chapter
Could you answer this?
Why is a three-body collision necessary to create carbon in stars?
✨ Stellar Nucleosynthesis
- 01The Coulomb BarrierWhy atoms resist fusing and the extreme pressures needed to force them together.
- 02Helium and the Triple-AlphaHow stars bridge the 'mass gap' to create carbon through rare, high-heat collisions.
- 03The Iron Dead-EndWhy fusing iron is a star's death sentence, leading to immediate core collapse.
- 04R-Process and SupernovaeThe violent birth of heavy metals like gold and uranium in cosmic cataclysms.
- 05Biological StardustTracing the path from stellar debris to the atoms in human DNA and blood.