Mercury Shrank More Than Thought, Losing Up to 14.5 Miles in Diameter

Researchers at the German Aerospace Center's Institute of Space Research revised estimates of Mercury's contraction: earlier calculations underestimated the shrinkage by 10 to 30%, meaning the planet lost up to 14.5 miles of its peak diameter over billions of years. The cause is a cooling, shrinking core, with wrinkle ridges and lobate scarps marking the surface.

• Previous shrinkage estimates were off by 10 to 30%
• Mercury lost up to 14.5 miles of its peak diameter
• Cooling and contraction of the planet's core drive the shrinkage
• Wrinkle ridges and lobate scarps mark the surface