A ___ System has a Star, Planets & Moons, as well as other space debris which all orbit the Star.
Planetary System
A ___ is a system of billions of stars, together with gas & dust, all held together by gravitational attraction.
Galaxy
What is the name of our galaxy?
The Milky Way
How big, in light years, is our galaxy?
100,000 light years
What galaxy is the closest to us?
The Andromeda Galaxy
The ____ is all existing matter & space considered as a whole.
Universe
The Universe is ___ billion light years in diameter.
10
How many main planets are in our Solar System?
8
How many moons are in our Solar System?
More than 200+
A moon is a natural ___ of a planet.
Satellite
How many millions of years does it take for our Solar System to orbit around the galactic center?
230
Which planet is the closest planet to our Sun?
Mercury
Mercury is the ____ planet in our Solar System (size).
Smallest
How long does it takes Mercury to orbit the Sun (make one revolution)?
88 Earth days
True or False: Mercury is the hottest planet in our Solar system?
False
True or False: One day-night cycle on Mercury takes 100 Earth days?
False
