Across
1
Positive particle in nucleus
4
Push or pull on an object
5
Fourth state of matter
7
Blocking of light by a celestial body
10
Gas essential for breathing
Down
2
Curved glass that refracts light
3
Nerve cell in the brain
6
Solid with repeating atomic pattern
8
Amplified beam of light
9
Molten rock beneath Earth surface
11
Ball of burning gas in space