How old is our solar system and universe?

• Our Sun is estimated to be 9 billion years old. Our universe is estimated to be 13 to 14 billion years old.

• Our Sun is estimated to be 4.6 billion years old. Our universe is estimated to be 13 to 14 billion years old.

• Our Sun is estimated to be 9 billion years old. Our universe is estimated to be 9 billion years old.

• Our Sun is estimated to be 4.6 billion years old. Our universe is estimated to be 9 billion years old.

What type of star is our sun? How is it classified?

• Our Sun is an average white star and is presently positioned on the main sequence.

• Our Sun is an average yellow star and is presently positioned on the main sequence.

• Our Sun is an average yellow star and is presently positioned on the white dwarfs.

• Our Sun is an average white star and is presently positioned on the white dwarfs.

What is the nature of our galaxy's shape?

• The shape of our galaxy is elliptical, with our solar system located on an outer arm of our rotating galaxy. It is theorized that galaxies rotate due to a supermassive black hole located at the center of all galaxies.

• The shape of our galaxy is elliptical, with our solar system located on an outer arm of our rotating galaxy. It is theorized that galaxies rotate due to a supermassive supergiant located at the center of all galaxies.

• The shape of our galaxy is spiral, with our solar system located on an outer arm of our rotating galaxy. It is theorized that galaxies rotate due to a supermassive supergiant located at the center of all galaxies.

• The shape of our galaxy is spiral, with our solar system located on an outer arm of our rotating galaxy. It is theorized that galaxies rotate due to a supermassive black hole located at the center of all galaxies.

Which star color indicates the hottest star surface temperature?

• blue

• white

• yellow

• red

Which location on the graph best represents a star with average brightness and temperature?

• A

• B

• C

• D

Which star is more massive than our Sun, but has a lower surface temperature?

• 40 Eridani B

• Aldebaran

• Barnard's Star

• Sirius

Which star is hotter and many times brighter than Earth's Sun?

• Barnard's Star

• Betelgeuse

• Rigel

• Pollox

Compared with our Sun, the star Betelgeuse is

• smaller, hotter, and less luminous

• smaller, cooler, and more luminous

• larger, hotter, and less luminous

• larger, cooler, and more luminous

Which two stars have the most similar luminosity and temperature?

• Betelgeuse and Barnard's Star

• Alpha Centauri and the Sun

• Rigel and Betelgeuse

• Sirius and Procyon B

Compared to the temperature and luminosity of the star Polaris, the star Sirius is

• hotter and more luminous

• hotter and less luminous

• cooler and more luminous

• cooler and less luminous