Across
1
Natural satellite of Earth
3
Force that attracts objects together
6
Icy body with a tail near the sun
8
Blocking of light by a celestial body
9
Naturally occurring inorganic solid
11
Molten rock beneath Earth surface
Down
2
Unit of electric potential
4
Path of a planet around the sun
5
Curved glass that refracts light
7
Gas essential for breathing
10
Disturbance that transfers energy