Astronomy Unit 2 Assessment

The four inner planets are rocky and small. Which description best fits the next four outer planets?

• They are also rocky and small.

• They are very large and made of ice.

• They are small and made of ice.

• They are very large and made of gases.

Which two planets are out of order in this list of our solar system? The planets are listed in order of distance from the sun.

Mercury-Earth-Venus-Mars-Jupiter-Saturn-Uranus-Neptune-Pluto

• Mercury and Earth

• Earth and Venus

• Saturn and Jupiter

• Uranus and Neptune

What is a special characteristic of Jupiter, Saturn, Neptune and Uranus?

• They are planets in our solar system.

• They spin slowly

• They revolve around the sun

• They have rings.

How does a telescope help us understand the moon?

• It tells us how it was formed.

• It tells us how hot it is there.

• It helps us see surface features.

• It can tell us what the moon is made of.

A probe landed on Mars and did soil tests. What information did it discover?

• There are no living organisms in Martian soil.

• Mars is slightly oval in shape.

• Mars is about one-fourth the size of Earth. D

• The gravity on Mars is much less than on Earth.

Pictures from space are sent to Earth. How are they printed?

• On paper from film sent from the probe.

• A computer reads a code and places dots on paper. C

• They are drawn by hand as the information is received.

• They are sent through space by rockets and are already printed.

Why is space travel difficult for people?

• We cannot take the air or food we need into space

• The distances are very great; it is dangerous and expensive.

• It is impossible to escape the sun’s or Earth’s gravity.

• We do not have a destination to visit that we know will support life.

What holds the planets in their orbits around the sun?

• gravity

• speed

• string

• air currents

Which object has the most gravity?

• Earth

• moon

• Jupiter

• sun

Without gravity, what would be the shape of the solar system?

• Planets would revolve in perfect circles.

• Much different than it is now.

• Planet’s orbits would cross.

• All planets would be in the same orbit.