Across
1
Measure of matter in an object
3
Unit of energy
5
Positive particle in nucleus
9
Blocking of light by a celestial body
10
Solid with repeating atomic pattern
12
Force that attracts objects together
Down
2
Preserved remains of ancient life
4
Our home planet
6
Mass per unit volume
7
Path of a planet around the sun
8
Smallest unit of an element
10
Reddish electrical conductor
11
Amplified beam of light