Reconstructing river flows remotely on Earth, Titan, and Mars.

Alluvial rivers are conveyor belts of fluid and sediment that provide a record of upstream climate and erosion on Earth, Titan, and Mars. However, many of Earth's rivers remain unsurveyed, Titan's rivers are not well resolved by current spacecraft data, and Mars' rivers are no longer active, hindering reconstructions of planetary surface conditions. To overcome these problems, we use dimensionless hydraulic geometry relations-scaling laws that relate river channel dimensions to flow and sediment transport rates-to calculate in-channel conditions using only remote sensing measurements of channel width and slope.