Ever seen a really dark night sky? The Globe at Night project is asking for volunteers to help it map the "illumination of sky by artificial sources," or light pollution. It even provides a handy interactive graphic to compare against your actual view.
Like the Galaxy Zoo project and distributed computing projects devoted to helping scientists search the sky for other life forms or model the performance of the Large Hadron Collider, these kinds of participatory science projects really appeal to me. You can help the Globe at Night from now until March 8. Hat tip: Universe Today
Image source: Visible Earth