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.