It almost never rains in Lima, the capital city of Peru, making it especially vulnerable to water shortages. The surprising solution might be reviving a system of ancient canals that date back to even before the Incas.
That intrepid, stare-off-into-the-distance look on Bill Gates's face? He is sipping on water that was, just a few minutes earlier, a pile of human waste. It's not just for laughs: the process shows how sewage can be transformed into water, electricity and fertiliser.
A worthy new crowdfunding project is taking on the ambitious job of solving the clean water crisis that affects large parts of the globe, claiming to use nothing more than the energy of the sun to purify dirty and salt water.
One problem that has been pointed out is that toxic wastewater is injected into wells that can leak and lubricate faults. We clearly need a better solution and that solution may involve satellite dishes.
This turquoise gem is what summer looks like in southeastern Alaska. From an altitude twice that of commercial jets, NASA's arctic research airplane ER-2 (a civilian version of the Air Force's U2-S reconnaissance plane) captured this view of a summertime melt pond atop a glacier on July 16, 2014.[NASA Earth Observatory]