_________________ and _________________ were the first to set their feet on the Moon.

_____________ invented telescope.

The earth takes ___________ days to complete one revolution around the Sun.

There are _________ planets in the solar system.

_______________ and comets are heavenly  bodies  in the solar system.

_____________ is the slowest rotating planet.

Pluto is called ____________ planet.

________________ planet is known as blue planet.

___________ is known as Earth's twin planet.

Moon is the satelite of  _______________