Across
1
Absolute temperature scale unit
3
Ball of burning gas in space
6
Path of a planet around the sun
8
Chemical element in table salt
11
Center of an atom or cell
Down
2
Disturbance that transfers energy
4
Element found in all living things
5
Substance with pH above 7
7
Preserved remains of ancient life
9
Hottest planet in solar system
10
The Red Planet
12
Substance with pH below 7