Across
1
Precious yellow metallic element
3
Natural satellite of Earth
6
Blocking of light by a celestial body
8
Path of a planet around the sun
10
Mass per unit volume
11
The Red Planet
Down
2
Chemical element in table salt
4
Smallest unit of an element
5
Substance with pH below 7
7
Force that attracts objects together
8
Compound containing oxygen
9
Solid with repeating atomic pattern