Across
1
Naturally occurring inorganic solid
4
Second lightest element
5
Icy body with a tail near the sun
6
Biological catalyst
7
Glass that splits light into spectrum
9
Force that attracts objects together
Down
2
Chemical element in table salt
3
Curved glass that refracts light
4
Form of thermal energy
6
Blocking of light by a celestial body
8
Our home planet