Comets lose material when they get near ___

• planets
• other comets
• the Sun
• the outer solar system

How long ago was our solar system formed?

• about 4.5 million years ago
• about 9.2 million years ago
• about 4.5 billion years ago
• about 9.2 billion years ago

Out in the chillier part of the Solar System, water came in the form of ___

• liquid water
• ice mixed with dust
• vapor mixed with dust
• water vapor

The discussed model, describing the evolution of the Solar System, was named after ___

• the city of Nice, France
• Neapolitan ice cream
• the city of Rome, Italy
• the planet Jupiter

During the formation of the Solar System, which planet had the biggest effect on the iceballs?

• Mars
• Saturn
• Uranus
• Neptune

The intense shower of objects that came screaming down from the outer solar system is called ___

• the Early Heavy Cataclysm
• the Late Heavy Cataclysm
• the Early Heavy Bombardment
• the Late Heavy Bombardment

The doughnut-shaped region, just past Neptune, where icy objects have stable orbits is called ___

• the Gerard Belt
• the Scattered Disk
• the Kuiper Belt
• the Kuiper Disk

The second region of objects, composed of iceballs with highly tilted orbits, is called ___

• the scattered disk
• the Kuiper disk
• the Kuiper Belt
• the concentrated ring

The scattered disk extends about ___ times farther out than Neptune.

• 2
• 5
• 25
• 50

The third region of icy objects, a spherical cloud which starts roughly 300 billion kilometers out, is called ___

• the Oort Cloud
• the Oort Disk
• the Kuiper Cloud
• the scattered disk