Planets

Scientists can easily compute the distance between planets.

Gravity binds the planets to the Sun.

This chapter will focus on the riddles of the planets.

He is always writing about journeying to other planets.

I wonder if life exists on other planets.

Is there life on other planets?

The sun has nine planets.

There are nine planets travelling around the sun, the earth being one of them.

The earth is different from the other planets in that it has water.

The earth is one of the sun's planets.