The sun is the prana of the universe,
And it rises to bring light to our eyes.
The earth draws the lower fire of apana:
The space between sun and earth is samana,
And the moving air is vyana.

Prana is the vital energy of the universe, also known as Chi or "The Force" in the Star Wars movies.  The sun is, of course, the source of the physical energy that powers the solar system.  It is also the source of spiritual energy that come from God, to the spiritual sun, then to us.