Light 'Em Up

"However Vast the Darkness, We Must Supply Our Own Light" - theme.

Save your light collecting ship from the vast, invading army.  Place mines to collect resources and cannons to stop the invaders.  Kill them all before time runs out and before you're overwhelmed.  
Tip - if you click on a tower and don't see the "ghost" image of it, it means you're not close enough to a placeable area.  Try zooming in closer to an asteroid field.