Evolution of Stars 31.2

Question 1

nebula

Answer 1

interstellar cloud of gas, ice, and dust

Question 2

main sequence

Answer 2

section of the H-R diagram that is plotted from the upper left to the lower right and contains 90 percent of all known stars

Question 3

giant star

Answer 3

late stage in a star’s life cycle that occurs when its hydrogen fuel is depleted, its core contracts, and its outer layers expand and cool

Question 4

white dwarf

Answer 4

giant star that has lost its outer layers, leaving behind a hot , dense core that continues to contract under gravity

Question 5

supernova

Answer 5

gigantic explosion of a star in which the temperature within the collapsing star reaches 10 billion K, can evolve into a neutron star

Question 6

neutron star

Answer 6

produced by a collapsing star when protons and electrons in the star’s core collide to form neutrons

Question 7

black hole

Answer 7

a region in space that is so dense that nothing can escape its inward pull of gravity

Question 8

photosphere

Answer 8

layer of the sun that emits light into space

Question 9

sunspots

Answer 9

darker, cooler areas of the Sun’s photosphere