23.3

Question 1

hydrostatic equllibrium

Answer 1

balance between gravity pulling inward and nuclear fusion pushing outward keeps a star the same size

Question 2

nebula

Answer 2

large cloud of interstellar gas in space where stars are born

Question 3

what is the first stage of stellar evolution

Answer 3

nebula

Question 4

protostar

Answer 4

center of a shrinking spinning nebula

Question 5

what is the second stage of stellar evolution

Answer 5

protostar

Question 6

when does a star enter the main sequence

Answer 6

when fusion begins and the star becomes stable

Question 7

when does fusion start

Answer 7

when temp in a protostar becomes hot enough

Question 8

what is the third stage of stellar evolution

Answer 8

main sequence

Question 9

which stars will leave the main sequence first

Answer 9

larger

Question 10

fourth stage of stellar evolution

Answer 10

giant

Question 11

giant

Answer 11

large and bright star whose core is comprised of hydrogen

Question 12

supergiants

Answer 12

100x the sun relatively cool

Question 13

planetary nebula

Answer 13

expanding shell of gases shed by a dying star

Question 14

white dwarf

Answer 14

small hot dim star that is leftover center of an old star

Question 15

nova

Answer 15

white dwarf star that explodes as it cools

Question 16

supernova

Answer 16

star