LIFE CYLCE OF A

NEBULA

• every star (no matter the mass) starts off as a nebula
• nebula is cloud of gas & dust spread out in a huge volume
• a star is born when gas and dust from a nebula become so dense and hot that nuclear fusion begins
• in the most dense area of of the nebula, gravity pulls gas and dust together to form a protostar

PROTOSTAR

• first stage of star cycle
• nuclear fusion begins in protostars
• stars with large mass live for about 10 million years

SUPERGIANT

• the sun is a supergiant
• High mass stars evolve quickly into supergiants
• when supergiants run out of fuel, they turn into supernovas

SUPERNOVA

• an explosion of a supergiant
• supernovas can turn into black holes or neutron stars

BLACK HOLES

• blacks holes have so much gravity that not even light can escale
• three types of holes: spiral, elliptical, and irregular
• the most massive stars become black holes when they die

NEUTRON STARS

• after a supergiant explodes, some of the material from the star is left behind and may form a neutron star
• a neutron star is simply the remains of a high mass star