Across
1
Biological catalyst
6
Glass that splits light into spectrum
7
Icy body with a tail near the sun
8
Basic unit of life
Down
1
Blocking of light by a celestial body
2
Force that attracts objects together
3
Particle of light
4
Measure of matter in an object
5
Group of similar cells
9
Center of an atom or cell
10
Amplified beam of light
11
Fourth state of matter