Why do stars twinkle but planets to not? Crossword

This printable crossword puzzle on the topic of Astronomy & Space has 10 clues. Answers range from 4 to 13 letters long. This crossword is also available to download as a Microsoft Word document or a PDF.

a type of science that manages objects outside the earths atmosphere
the twinkling of stars
something that shines repeatedly
a bright light in the night sky
a celestial that orbits the sun
an aggressive motion of water and/or air
light passing through a medium with a different density
gases that surround the earth and other planets
an agent that encourages sight and helps us see
a substance that fills any and all available space