Across
1
Curved glass that refracts light
3
Particle of light
6
Gas essential for breathing
7
Second lightest element
Down
2
Compound containing oxygen
4
Natural satellite of Earth
5
Blocking of light by a celestial body
7
Form of thermal energy
Curved glass that refracts light
Particle of light
Gas essential for breathing
Second lightest element
Compound containing oxygen
Natural satellite of Earth
Blocking of light by a celestial body
Form of thermal energy