|On average, Earth is ____ million miles (1 AU) from the Sun.
|Earth rotates about ____ times per orbit around the Sun.
|The Moon is ____ times larger than the dwarf planet Pluto.
|The Big Bang occurred a little less than ____ billion years ago.
|About ____ planets have been discovered in the Milky Way.
|There are ____ planets in the Solar System.
|Earth is almost ____ times larger than the Moon.
|The Sun is about ____ times larger than the Earth.