Across
1
Nerve cell in the brain
5
Amplified beam of light
6
Particle of light
7
Smallest unit of an element
8
Unit of force
10
Solid with repeating atomic pattern
12
Blocking of light by a celestial body
Down
2
Absolute temperature scale unit
3
Positive particle in nucleus
4
Gas essential for breathing
9
Reddish electrical conductor
11
Path of a planet around the sun