Across
1
Infectious microscopic agent
3
Smallest unit of an element
6
Tectonic landmass section
7
Icy body with a tail near the sun
8
Form of thermal energy
9
Amplified beam of light
10
Chemical element in table salt
12
Particle of light
13
Biological catalyst
Down
2
Second lightest element
4
Blocking of light by a celestial body
5
Molten rock beneath Earth surface
11
Unit of electric potential