Across
1
Particle of light
3
Our home planet
5
Measure of matter in an object
6
Tissue that contracts for movement
7
Magnetic metallic element
9
Smallest unit of an element
11
Positive particle in nucleus
Down
1
Tectonic landmass section
2
Unit of force
4
Path of a planet around the sun
5
The Red Planet
8
Biological catalyst
10
Icy body with a tail near the sun
12
Force that attracts objects together
13
Naturally occurring inorganic solid