Across
1
Amplified beam of light
4
Molten rock beneath Earth surface
6
Blocking of light by a celestial body
7
Chemical element in table salt
8
Unit of electric potential
10
Substance with pH below 7
Down
2
Biological catalyst
3
Our home planet
5
Solid with repeating atomic pattern
9
Naturally occurring inorganic solid
11
Natural satellite of Earth
12
Element found in all living things
13
Group of similar cells