High mass stars After the main sequence, stars with a mass much greater than the sun can burn and create larger and larger elements When it gets to iron, it takes too much energy to create other elements so it collapses This causes a supernova, this is when heavier elements are made

Large Mass Stars have a different fate When they get to iron, it takes more energy so the star collapses and then rebounds This causes a supernova Generate the elements of life The inner part implodes to form a super dense neutron star

How is the Life cycle of a high mass different???? Starts the same but burns faster and ends differently Either –Supernova –Supernova then Neutron star black hole

Lab—HR diagram Study lists and answer 21.1 &21.2 Temp on horizontal Absolute magnitude on vertical Note graph lines are not equal Chart nearest stars with a (+) sign Chart brightest stars with a Show stars on both as circled + Use an * to show the sun on the diagram

Pulsars emit low frequency radio transmissions –A few emit X-rays or visible light –The picture to the left is a gamma ray burst animation

Extremely Massive stars Extremely massive stars that undergo gravitational collapse may become a

Black Holes Singularity — density is infinite

Event horizon—point of no return

Gravity Lensing — or how we know where they are Image copyright © 1998 by John Chang. Chang

NASA Life Cycle of Stars Review