Across
1
Ball of burning gas in space
2
Push or pull on an object
3
Chemical element in table salt
5
Blocking of light by a celestial body
7
Unit of heredity
9
Our home planet
10
Particle of light
11
Solid with repeating atomic pattern
Down
2
Preserved remains of ancient life
4
Unit of energy
6
Tissue that contracts for movement
8
Element found in all living things
12
Compound containing oxygen
13
Substance with pH above 7