Across
1
Hottest planet in solar system
4
Path of a planet around the sun
6
Smallest unit of an element
7
Absolute temperature scale unit
10
Blocking of light by a celestial body
12
Unit of power
Down
2
Center of an atom or cell
3
Glass that splits light into spectrum
5
Unit of electric potential
8
Force that attracts objects together
9
Compound containing oxygen
10
Biological catalyst
11
Fourth state of matter