Across
1
Icy body with a tail near the sun
4
Particle of light
5
Curved glass that refracts light
7
Disturbance that transfers energy
8
Precious yellow metallic element
9
Fourth state of matter
Down
2
Group of similar cells
3
Positive particle in nucleus
5
Amplified beam of light
6
Absolute temperature scale unit
9
Tectonic landmass section
10
Reddish electrical conductor