Across
1
Tectonic landmass section
3
Molten rock beneath Earth surface
6
Absolute temperature scale unit
7
Compound containing oxygen
8
Nerve cell in the brain
9
Hottest planet in solar system
Down
2
Precious yellow metallic element
4
Fourth state of matter
5
Blocking of light by a celestial body
10
Second lightest element
11
Biological catalyst