Stars and Star Formation

The Sun is a ______ just like the other stars that you see twinkling in the night. (Fill in the blank)

Why do stars appear to twinkle?

• Because they are moving rapidly

• Because we are looking through the atmosphere at a star

• Because they are cooling down

• Because they are close to the Earth

Stars are balls of extremely hot ______.

• gasses

• liquids

• rocks

• ice

What is the temperature at the center (core) of a star?

• 1 million degrees

• 5 million degrees

• 15 million degrees

• 100 million degrees

Two hydrogen atoms (atomic #1) fuse together in nuclear fusion to produce ______ atoms (atomic #2).

• helium

• carbon

• oxygen

• lithium

When the energy of fusion, pushing out, and the force of gravity, pushing in, equal each other, the star becomes stable and enters its first stage as a star. What is this stage called?

• the main sequence

• the red giant phase

• the white dwarf stage

• the supernova stage

The Sun is a ________ star.

• main sequence

• red giant

• white dwarf

• neutron

What percentage of our galaxy is made of main sequence stars?

• 90%

• 10%

• 50%

• 30%

The Sun is average size and temperature for a ________ sized star.

• medium

• giant

• dwarf

• supergiant

What class of star is the Sun?

• class G

• class M

• class O

• class B