Across
1
Unit of force
5
Nerve cell in the brain
8
Infectious microscopic agent
9
Particle of light
11
Blocking of light by a celestial body
13
Gas essential for breathing
Down
2
Hottest planet in solar system
3
Disturbance that transfers energy
4
Center of an atom or cell
6
Precious yellow metallic element
7
Icy body with a tail near the sun
10
Mass per unit volume
11
Our home planet
12
Positive particle in nucleus