Across
1
The Red Planet
2
Tectonic landmass section
3
Compound containing oxygen
5
Group of similar cells
7
Path of a planet around the sun
9
Measure of matter in an object
10
Basic unit of life
11
Curved glass that refracts light
Down
2
Glass that splits light into spectrum
4
Blocking of light by a celestial body
6
Particle of light
8
Smallest unit of an element
12
Preserved remains of ancient life