The Known Universe
Zoom from the Himalayas to the edge of the observable Universe—and back again.
China's Acidic Farmland
Reliance on chemical fertilizer in China may deplete its critical farmland.
Our Expanding Universe
The universe is expanding at an ever-faster rate — a phenomenon that can't be explained by our current understanding of gravity. Is dark energy to blame? Or do we need to rework gravitational theory?
