The Circle of Life
This is the primary factor that determines the specific life path a star will take and how long it will live.
Initial Mass
This is the primary energy source (fusion sequence) for stars with masses less than 1.5 times the mass of the Sun.
Proton-proton chain
This is the extremely dense, hot core remnant left behind after a low-mass star sheds its outer layers.
White Dwarf
This is the star's visible "surface" from which light finally escapes into space.
Photosphere
This state of balance exists when the outward pressure of fusion perfectly counters the inward pull of gravity.
Hydrostatic (or Thermo-gravitational) Equilibrium
Stars spend about 90% of their lives in this stable phase, fusing hydrogen into helium.
Main Sequence
This fusion cycle is dominant in massive stars and uses Carbon, Nitrogen, and Oxygen as catalysts.
CNO cycle
This is the catastrophic explosion that marks the death of a massive star.
Supernova
These dark, cooler regions on the photosphere are caused by localized magnetic fields.
Sunspots
This quantum mechanical effect occurs when electrons resist being squeezed into the same volume, supporting White Dwarfs.
Electron Degeneracy
This is the pre-main sequence stage where a dense core of a molecular cloud collapses and begins to heat up.
Protostar
Once a massive star's core has fused elements up to this specific metal, it can no longer produce energy through fusion.
Iron
This is a region of spacetime with gravity so intense that not even light can escape.
Black Hole
In this layer, energy is transported by massive circulating currents, similar to a pot of boiling water.
Convection Zone
This type of degeneracy pressure supports the ultra dense core left behind after a Type II Supernova.
Neutron Degeneracy
This term describes the precise moment a star first begins stable core hydrogen fusion.
Zero-Age Main Sequence
Due to the "random walk" through dense layers, it can take a photon up to this long to travel from the core to the surface.
tens of thousands to over a million years
This is the name for the maximum mass (1.4 solar masses) a white dwarf can have before it collapses.
Chandrasekhar Limit
This is the star's tenuous, outermost atmosphere that is surprisingly hotter than the surface.
Corona
These vast, cold regions of interstellar gas and dust (mostly hydrogen) are the birthplaces of stars.
Giant Molecular Clouds
These are often called "failed stars" because their mass is too low (less than 0.08) to ever ignite hydrogen fusion.
Brown Dwarfs
Once a photon finally escapes the Sun’s surface, it takes approximately this long to reach Earth.
8.2-8.4 Seconds
This is a sudden, bright flare-up on a white dwarf's surface caused by accreting hydrogen from a companion star.
Nova
This layer surrounds the core and transports energy through the continuous absorption and re-emission of photons.
Radiation Zone
This thin, reddish layer of the atmosphere is typically only visible during a total solar eclipse.
Chromosphere