Stellar Evolution

A cloud of dust and gas found in space is known as a(n) ___________. 

• space cloud
• nebula
• black hole
• galaxy

A collapsing cloud of dust and gas considered to be the earliest stage in a star's life is called a(n) _____________. 

• nebula
• main sequence star
• protostar
• neutron star

The process of ________________ begins when the core of a protostar reaches 10 million K

• nuclear fission
• hydrogen burning
• nuclear fusion
• spectroscopy

All stars spend about 90% of their life cycle in this stage of stellar evolution. 

• supergiant
• neutron star
• planetary nebula
• main sequence

What is the main source of fuel when a star is in the main sequence? 

• oxygen-burning
• hydrogen-burning
• electromagnetic radiation
• high amounts of energy under intense heat and pressue

Which of the following states the correct relationship between the size of a star and how long it will last? 

• low mass stars only last for a few million years while high mass stars last for billions of years
• low mass and high mass stars last for the same amount of time
• low mass stars last for billions of years while high mass stars last for millions of years
• it is completely random how long a star will last regardless of its size

Low mass stars will exit the main sequence and become ___________. 

• supergiants
• planetary nebulae
• white dwarves
• black holes

Medium mass stars such as our sun exit the main sequence to become _________. 

• white dwarves
• neutron stars
• black holes
• red giants

After hydrogen runs out which element will be fused first?

• Carbon

• Helium

• Iron

• Silicone

Stars with a mass 3 times greater than our sun or higher will die in a violent explosion called a(n) ______________. 

• supernova

• black hole

• detonation

• shell burn