Name the unit which is used to express distances between the various celestial bodies (like stars and planets).
Fill in the blanks.
(a) A group of ________ forming various patterns is called a ________.
(b) A huge system of stars is called _________.
(c) ________ is the closest celestial body to our Earth.
(d) ________ is the third nearest planet to the Sun.
(e) Planets do not have their own _________ and __________.
Planets, stars, other solar systems and celestial bodies are found in a vast expanse called: