Unit 4, Lessons 1-3 (Gravity, Stars, Day/Night)

What is the apparent brightness of a star a measure of?

• How bright it looks from Earth

• How much light it emits

• How far it is from the Sun

Why is the sun so much brighter than other stars?

• Because it is closer to Earth

• Because it is larger than other stars

• Because it emits more light

Which star is one of the closest to Earth and appears much dimmer than the sun?

• Alpha Centauri A

• Sirius

• Betelgeuse

Why do stars that are a great distance from Earth look dimmer than stars that are closer?

• Because less of their light reaches Earth

• Because they are smaller

• Because they emit less light

What can scientists infer about a star based on its color?

• A) The star's distance from Earth

• B) The star's temperature

• C) The star's age

• D) The star's size

Which color of star is the hottest according to the text?

• A) Red

• B) Yellow

• C) Blue

• D) White

What unit is often used to measure the distance between stars?

• Kilometers

• Light years

• Astronomical units

• Miles

Why can we see the Sun during the day but not other stars?

• The Sun is the only star in our solar system.

• The Sun's light is blocked by the Moon.

• The Sun's light is much brighter because it's closer, overpowering other stars' light.

• Other stars do not emit light during the day.

How does the Sun's mass compare to other stars?

• It is the heaviest star known.

• It is of average mass for a star.

• It is the lightest star known.

• It is one of the heaviest stars known.

What is the effect of the Sun's proximity on its apparent brightness?

• The closer a star, the dimmer it appears.

• The closer a star, the brighter it appears.

• Distance has no effect on a star's brightness.

• The Sun's proximity makes it appear dimmer than it is.