Across
1
Center of an atom or cell
6
Absolute temperature scale unit
7
Positive particle in nucleus
9
Tectonic landmass section
10
Path of a planet around the sun
11
Unit of power
Down
2
Our home planet
3
Curved glass that refracts light
4
Push or pull on an object
5
Mass per unit volume
8
Unit of force
9
Glass that splits light into spectrum