Across
1
Unit of force
4
Infectious microscopic agent
7
Icy body with a tail near the sun
8
Our home planet
9
Disturbance that transfers energy
11
Center of an atom or cell
Down
2
Blocking of light by a celestial body
3
Path of a planet around the sun
5
Nerve cell in the brain
6
Gas essential for breathing
10
Particle of light
12
Substance with pH below 7
13
Curved glass that refracts light
14
Magnetic metallic element