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

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

Mercury and Earth
Earth and Venus
Saturn and Jupiter
Uranus and Neptune

2. Mary looked in her science book at a picture of the solar system. The planets were large and colorful but she knew it was not an accurate model. Why?

The planets should have been much farther apart
The planets are not colorful. They are white
We don't know exactly what the planets look like, so it was a guess
Planets are oval and not round

3. 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 gasses

4. Based upon the scale chart of planet size, how many cm less is Earth than Jupiter?

21.4 cm
17.7 cm
6.3 cm
2.4 cm

5. A probe from Earth has landed on an unknown object. Information sent to Earth describes the object as; mostly rock, some traces of metal, irregular shaped, and orbiting around the sun. From the previous information, what would you conclude this object might be?

a comet
an asteroid
a meteorite
a star

6. How can you tell comets from other objects in the Solar System?

Comets are generally made of ice and rock, have an oval-shaped orbit, and appear to have a tail.
Comets are made of iron and copper, are flourecent, and are the size of sand grains.
Comets are made of luminous materials and always orbit between Mars and Jupiter.
Newspapers and magazines have printed information about them.

7. What is one reason satellites are important to modern communication systems?

They are less expensive than phones.
They raise computer use expenses.
They relay television signals.
They cause air pollution.

8. The discovery of non-light emitting celestial bodies were found mainly through computers and

the Hubble telescope
the International Space Station
the optical telescope
the radio telescope

9. What is one way space technology is different than space exploration?

Technology makes use of what scientists discover in space.
Technology is concerned with theories only.
Technology is about the history of space.
Technology is used only in earth exploration.

10. We can retrieve data from objects in outer space. Which of the following would be almost impossible to learn?

the highest and lowest temperature on Venus.
how long it takes the planets to move around the Sun.
how many stars there are in our Galaxy.
the time it takes for light to travel from the Sun to Earth.

11. What is an important function of space probes, such as Voyager, as they travel in space?

To land on each planet and report the conditions there
To take pictures and send them back to Earth
To analyze what each planet is made of
To see if life exists on other planets

12. Compare the gravity on the Earth and the moon to determine which statement is correct.

The moon orbits the Earth because they have an equal gravitational pull on each other
The moon and Earth do not collide because the gravitational force of each pushes them apart
The gravity of the Earth and the moon pulls them together, but Earth's gravity is greater because it has more mass
The Earth and moon do not collide because the Earth has greater mass and, therefore, greater gravity than the moon and pushes it away

13. What do objects that have more mass also have more of?

volume
size
gravity
speed

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

Planets would revolve in perfect circles.
It would be much different from what it is now.
Planets' orbits would cross.
All planets would be in the same orbit.