The Universe

A large artificial satellite on which people can live for long periods is a space station.

This is the largest and most massive planet.

Areas of gas on the sun's surface that are cooler than the gases around them.

The movement of Earth around the sun once a year is called Earth's

All terrestrial planets are surrounded by rings.

This gas giant's axis is believed to be tilted due to an impact by another object.

This planet is known as the "evening star" or "Earth's twin."

This planet's atmosphere is so thick it is always cloudy there.

These are collections of ice, dust, and small rocky particles.

The region between Mars and Jupiter where many rocky objects are found is the

This inner planet has virtually no atmosphere causing it to have great temperature ranges.

This planet is known for its spectacular rings made of chunks of ice and rock.

This moon of Jupiter has an icy crust covering an ocean of liquid water underneath.

Olympus Mons, the largest volcano in the solar system, is found on this planet.

The craters on Earth's moon were caused by

What characteristics do all of the inner planets share?

A spacecraft that can carry a crew into space, return to Earth, and be reused again

This moon, belonging to Jupiter, is covered with large, active volcanoes.

This cold, blue planet's atmosphere contains visible clouds.

Meteoroids that pass through the atmosphere and hit Earth's surface are called

The trapping of heat by a planet's atmosphere is called

This is the largest moon in the solar system. It is larger than Mercury or Pluto.

Scientists predict that this moon will eventually smash into Mars in about 40 million years.

The shape of the orbit of each planet is a(n)

Which of these planets' orbits is farthest from the Earth's orbit?

Any object that revolves around another object in space is called a

When a meteoroid enters Earth's atmosphere, it becomes known as a

This is Saturn's largest moon. Its atmosphere is so thick that little light can pass through.

Pluto is a(n)

When gas on the sun heats and erupts into space it is called a