Across
1
Gas essential for breathing
4
Measure of matter in an object
5
Unit of power
7
Glass that splits light into spectrum
8
Solid with repeating atomic pattern
Down
2
Icy body with a tail near the sun
3
Amplified beam of light
6
Infectious microscopic agent
9
Blocking of light by a celestial body
10
Our home planet
11
Group of similar cells