Across
1
Preserved remains of ancient life
3
The Red Planet
4
Path of a planet around the sun
5
Curved glass that refracts light
6
Ball of burning gas in space
9
Solid with repeating atomic pattern
10
Basic unit of life
12
Blocking of light by a celestial body
Down
2
Group of similar cells
3
Tissue that contracts for movement
7
Unit of electric potential
8
Amplified beam of light
11
Absolute temperature scale unit
13
Unit of force