Across
1
Glass that splits light into spectrum
4
Center of an atom or cell
5
Naturally occurring inorganic solid
6
Gas essential for breathing
9
Solid with repeating atomic pattern
10
Group of similar cells
12
Ball of burning gas in space
Down
2
Force that attracts objects together
3
Blocking of light by a celestial body
5
Measure of matter in an object
7
Natural satellite of Earth
8
Unit of heredity
11
Preserved remains of ancient life