Across
1
The Red Planet
3
Blocking of light by a celestial body
5
Unit of heredity
6
Reddish electrical conductor
7
Magnetic metallic element
8
Form of thermal energy
10
Positive particle in nucleus
11
Curved glass that refracts light
Down
1
Molten rock beneath Earth surface
2
Nerve cell in the brain
4
Ball of burning gas in space
6
Solid with repeating atomic pattern
9
Compound containing oxygen
12
Absolute temperature scale unit