Across
1
Measure of matter in an object
3
Solid with repeating atomic pattern
4
Unit of heredity
9
Ball of burning gas in space
10
Smallest unit of an element
Down
1
The Red Planet
2
Blocking of light by a celestial body
5
Gas essential for breathing
6
Substance with pH below 7
7
Push or pull on an object
8
Path of a planet around the sun