Across
1
Positive particle in nucleus
4
Blocking of light by a celestial body
5
Unit of energy
9
Path of a planet around the sun
10
Natural satellite of Earth
Down
2
Infectious microscopic agent
3
Icy body with a tail near the sun
6
Compound containing oxygen
7
Nerve cell in the brain
8
Particle of light
11
Precious yellow metallic element