Across
1
Particle of light
3
Basic unit of life
5
Molten rock beneath Earth surface
7
Substance with pH above 7
8
Blocking of light by a celestial body
Down
2
Compound containing oxygen
4
Gas form of a liquid
5
Measure of matter in an object
6
Hottest planet in solar system
9
Force that attracts objects together
10
Ball of burning gas in space