April 22 is traditionally known as Earth Day, the occasion where we pause as temporary travelers on our ' blue marble ' to honor and respect our precious planetary home and its immeasurable beauty, allowing for greater appreciation of this distinctive world's bounty of resources.

For the 55th year, the world is using the day to celebrate Mother Nature and the wonderful planet we live on. "Earth Day really is a symbol of the environmental movement," Sarah Davies, the director of communications and media at EarthDay.

The 55th Earth Day is Tuesday, and the theme this year focuses on renewable energy — “Our Power, Our Planet.” Today we look at renewables in the U.S. Renewable energy resour