Mr. Fetch's Earth Science Class Stars: A ball of burning gas. Mr. Fetch's Earth Science Class Mr. Fetch’s Earth Science Classroom A+

A+ Life Cycles: Birth, Life, and Death of a Star Shockwave Gravity compresses star Heats up fusion begins, pressure balances with gravity. Hydrogen is burning and balancing out the compression from gravity. Mr. Fetch's Earth Science Class Mr. Fetch’s Earth Science Classroom A+

Mr. Fetch's Earth Science Class Star live happy until it uses up its food: Hydrogen Stars live happy until they run out of food. It can no longer overcome gravity and starts to compress again. Bigger stars need more food to overcome gravity and thus use up there food faster (die earlier). A dying star changes from a main sequence start to another type of star. Depending on the mass of the star. Mr. Fetch's Earth Science Class Mr. Fetch’s Earth Science Classroom A+

Mr. Fetch's Earth Science Class Mr. Fetch’s Earth Science Classroom A+

Mr. Fetch's Earth Science Class Medium Mass Stars (like the sun). Star compresses and heats up so much that the Helium produced during fusion now begins to burn. This causes the outer atmosphere of the start to be wisped off into space leaving just the stars core behind. This core is called a white dwarf. White dwarfs are the same size as earth but way more dense. Mr. Fetch's Earth Science Class Mr. Fetch’s Earth Science Classroom A+

Mr. Fetch's Earth Science Class High Mass Stars Stars burn H and He so fast cause they are so large. They are burning hotter and so they burn even heavier elements than He. This continued fusion causes the star to expand quickly into a super-giant. Fusion continues until elements in the core can no longer be burnt (Fe)… and then gravity overcomes the star and it compresses and explodes as a supernova explosion. After the explosion, the core of the star remain and becomes either a black hole or a neutron star depending on just hot massive it is. Mr. Fetch's Earth Science Class Mr. Fetch’s Earth Science Classroom A+

Supernova

A+ 1.4 to 3 times the mass of the sun Neutron Star From a Supernova… now what? 1.4 to 3 times the mass of the sun Neutron Star Greater than 3.0 the mass of the sun. Black Hole Mr. Fetch's Earth Science Class Mr. Fetch’s Earth Science Classroom A+

Mr. Fetch's Earth Science Class Neutron Stars Small Extremely Dense - teaspoon weighs a mountain Stupendous surface gravity Rotate 1000 times per second (pulsar) marshmallow 3-megaton explosion neutron star Mr. Fetch's Earth Science Class Mr. Fetch’s Earth Science Classroom A+

Mr. Fetch's Earth Science Class Black Holes Massively dense core of a dead star compressed to a speck. There is an imaginary sphere around the black hole called an event horizon. Anything that goes into the event horizon can not escape its stupendous gravity. Mr. Fetch's Earth Science Class Mr. Fetch’s Earth Science Classroom A+

Mr. Fetch's Earth Science Class Black Holes event horizon BH Mr. Fetch's Earth Science Class Mr. Fetch’s Earth Science Classroom A+