Across
1
Our home planet
4
Second lightest element
5
Form of thermal energy
6
Natural satellite of Earth
7
Chemical element in table salt
10
Ball of burning gas in space
Down
2
Particle of light
3
Naturally occurring inorganic solid
8
Hottest planet in solar system
9
Glass that splits light into spectrum
11
Unit of electric potential
12
Path of a planet around the sun