Summary:
- This article discusses the discovery of "ghost rivers" - river channels that appear to have flowed in the past but don't have any visible water flow today.
- Scientists used satellite imagery and computer models to identify these ghost rivers in the Sahara Desert, which was once a lush, green landscape thousands of years ago.
- The discovery of these ancient river channels provides important clues about how the climate and environment of the Sahara have changed over time, and helps scientists better understand the region's complex history.