Across
1
Nerve cell in the brain
4
Solid with repeating atomic pattern
6
Compound containing oxygen
7
Disturbance that transfers energy
8
Blocking of light by a celestial body
11
Measure of matter in an object
Down
2
Ball of burning gas in space
3
Mass per unit volume
4
Reddish electrical conductor
5
Hottest planet in solar system
7
Unit of power
9
Molten rock beneath Earth surface
10
Biological catalyst
12
Icy body with a tail near the sun
13
Tectonic landmass section