Here's where it all begins: home sweet Earth. While we humans have only set foot on the planet we sprang from and one solitary moon, we've constructed probes, orbiters, and rovers to saunter out into space and send back their reports. The following photos show some of the most exciting stops along humanity's (mostly vicarious) march through the solar system.

This July 2003 picture was taken by astronauts on the International Space Station, our first attempt at a permanent space habitat. The photo shows the tops of huge, anvil-shaped thunderheads far above the Pacific Ocean.