The life cycle of stars from birth to death
Stellar Evolution The life cycle of stars from birth to death Nebula condense by accretion
Event (shock wave, super nova, etc) triggers nebula collapse ->fusion -> a star
Gas & dust attracts due to gravity Contracting matter causes a spinning & flattening Large clump in center = forming star Flat accretion disc = planets When fusion begins, stellar wind pushes out un-clumped matter and gravitational collapse stops nebula Protostar and disc Gravity & heat ->fusion -> a star Protostar =forming star; not yet fusing
glows frompressure/frictiontemperatures (not shining) Thermonuclear Fusion Enough heat & gravity = atoms smashed into each other Universe~80% Hydrogen (H) + 20% Helium (He) + Dust H + HHe + light & heat(Star shines!) Neutrinonearly massless particle with no charge Positron- opposite of an electron; positively charged. Brown Dwarf? = a failed star; never started fusion
Not enough mass innebula to createenough gravity,pressure andtemperature to startfusion