Across
1
Positive particle in nucleus
5
The Red Planet
6
Blocking of light by a celestial body
7
Form of thermal energy
8
Biological catalyst
9
Unit of force
Down
1
Tectonic landmass section
2
Unit of heredity
3
Amplified beam of light
4
Mass per unit volume
10
Chemical element in table salt
11
Path of a planet around the sun
12
Substance with pH above 7