Slow-churning convection cells constantly renew the surface
The western lobe of Pluto's heart-shaped Tombaugh Regio is a vast plain of frozen nitrogen called Sputnik Planitia. Warmth from Pluto's interior makes the soft nitrogen ice rise and sink in giant cells, churning like a lava lamp and dividing the plain into a patchwork of polygons. This recycling erases impact scars, leaving a surface estimated at less than about 10 million years old — a sign Pluto is still geologically active today.
