G5 The Solar System 1

A ______ is a huge system of stars, gas, and dust held together by gravity.

• constellations

• universe

• star

• galaxy

A huge ball of hot glowing gases that release energy is known as a ___________.

• constellations

• universe

• star

• galaxy

The _______ is everything in space.

• constellations

• universe

• star

• galaxy

Group of stars that appear to make imaginary shapes or patterns are called _______.

• constellations

• universe

• star

• galaxy

Select the true statements.

• The hottest stars are blue.

• The hottest stars are red.

• The coolest stars are blue.

• The coolest stars are red.

Which statement is true?

• A light-year is the time it takes the Moon to circle Earth.

• A light-year is the time it takes Earth to circle the Sun.

• A light-year is the distance light travels in one year.

• A light-year is the time it takes for light to travel 1km.

The nearest star to Earth is the _____.

• Moon

• Sun

• Mars

• Venus

Ancient navigators used the North Star to navigate because it is almost directly above the north pole, when you see it in the sky you can always determine which way is north.

• True

• False

Why do stars seem to move from east to west across the sky?

• The Earth spins around the Sun.

• The spinning of Earth makes the stars appear to move.

• The Sun makes the stars appear to move.

How are objects in galaxies held together?

• Over time, most of the mass of the Sun is converted to light and heat.

• From the gravity of the Sun.

• Objects in galaxies held together by the gravity in the galaxy.