Across
1
Unit of force
4
The Red Planet
5
Naturally occurring inorganic solid
7
Icy body with a tail near the sun
9
Unit of power
Down
2
Positive particle in nucleus
3
Preserved remains of ancient life
6
Curved glass that refracts light
7
Basic unit of life
8
Fourth state of matter
10
Smallest unit of an element
11
Biological catalyst