Across
1
Center of an atom or cell
3
Force that attracts objects together
6
The Red Planet
8
Magnetic metallic element
9
Molten rock beneath Earth surface
11
Preserved remains of ancient life
12
Positive particle in nucleus
Down
2
Tectonic landmass section
4
Path of a planet around the sun
5
Glass that splits light into spectrum
7
Gas essential for breathing
10
Chemical element in table salt