Across
1
Path of a planet around the sun
3
Particle of light
7
Icy body with a tail near the sun
8
Amplified beam of light
9
Ball of burning gas in space
Down
1
Gas essential for breathing
2
Smallest unit of an element
3
Fourth state of matter
4
Substance with pH above 7
5
Gas form of a liquid
6
Tectonic landmass section