Across
1
The Red Planet
4
Blocking of light by a celestial body
6
Tectonic landmass section
8
Center of an atom or cell
9
Group of similar cells
11
Unit of electric potential
Down
2
Solid with repeating atomic pattern
3
Preserved remains of ancient life
5
Unit of force
7
Compound containing oxygen
10
Form of thermal energy
12
Amplified beam of light