LIFECYLE OFLARGE STARS

STAGE 1: NEBULAThere are numerous giganticclouds of dust and gas(mostly hydrogen) spreadacross freezing coldinterstellar space. They arecalled “Nebulae”.

STAGE 2:PROTOSTAR

The cloud of dust and gasgathers together due to

gravity by virtue of its mass.At the center of this cloud

forms, what is known asa “Protostar”.

STAGE 3: MAINSEQUENCE STARA main sequence star is agigantic sphere in space,fusing hydrogen into heliuminside its core and using thisenergy released in the fusionreaction to counteract its owngravity (which is trying tocrush it).

STAGE 4: REDSUPERGIANT

Due to energy released inthe fusion reaction taking

place at the layers justabove the core, the

outermost layers of the starexpand and the star

becomes what is known asa “Red Supergiant”.

LIFECYLE OFLARGE STARSCONTINUED

STAGE 5:SUPERNOVA A supernova is an explosionin which a star explodesand expels its outer layersleaving a core behind tocollapse in on itself.

STAGE 6 A:NEUTRON STAR

A neutron star is a core of astar after the supernova

which can have a mass up to2.17 solar masses. They are

very dense as the whole massof the star is compressed to

the size of a city.

STAGE 6 B:BLACK HOLE If the mass of theprogenitor star is more than10-29 solar masses its corecollapses into itself andforms what is known as a"Black hole" after thesupernova explosion.

SOURCES:

SPACEPLACE.NASA.GOVNASA.GOV