Across
1
Natural satellite of Earth
2
Force that attracts objects together
5
Path of a planet around the sun
7
Center of an atom or cell
Down
2
Unit of heredity
3
Push or pull on an object
4
Chemical element in table salt
6
Fourth state of matter
8
Blocking of light by a celestial body
9
Tectonic landmass section
10
Mass per unit volume