Stars and galaxies

The color of a star depends on its

• size

• temperature

• shape

• magnitude

What type of galaxy has no special shape or form?

• a spiral galaxy

• an elliptical galaxy

• an irregular galaxy

A supernova is the explosion of a dying:

• medium-mass star

• high-mass star

• protostar

• low-mass star

What type of galaxy is oval-shaped?

• a spiral galaxy

• an elliptical galaxy

• an irregular galaxy

What is the name of the largest stars?

• Protostars
• Supergiants
• Red Giants
• Dwarf Stars

About 90 percent of the stars in the universe, including the sun, are main sequence stars. What do all main sequence stars have in common?

• All main sequence stars are yellow like our sun.

• All main sequence stars are as bright as our sun.

• They are all undergoing fusion of helium into carbon within their cores

• They are undergoing fusion of hydrogen into helium within their cores

On an HR diagram, stars at the same temperature are found...

• aligned horizontally (next to each other)

• aligned vertically (one above the other)

• along the main sequence

• spread through the diagram

A large group of stars, gas, and dust is called....

• a universe

• a cluster

• a galaxy

• a solar system

A star is born in a cloud of gas and dust called a __________.

• nebula

• galaxy

• asteroid

• black hole

How are galaxies alike?

• The are all the same shape

• They have the same amount of stars

• They all have stars, gas, and dust

• They are all the same temperature