Across
1
Center of an atom or cell
3
Molten rock beneath Earth surface
6
Amplified beam of light
8
Unit of electric potential
9
Element found in all living things
10
Magnetic metallic element
11
Fourth state of matter
12
Blocking of light by a celestial body
Down
2
Disturbance that transfers energy
4
Positive particle in nucleus
5
Basic unit of life
7
Naturally occurring inorganic solid