The surface age of Sputnik Planum, Pluto, must be less than 10 million years

TL;DR

The paper estimates that Sputnik Planum's surface on Pluto is less than 10 million years old, indicating recent active resurfacing likely driven by cryo-geophysical processes, based on crater absence and impact rate data.

Contribution

It combines geological and telescopic data to provide the first order magnitude estimate of Sputnik Planum's surface age, suggesting active geological processes.

Findings

No craters detected down to 2 km, indicating recent resurfacing.

Surface age estimated to be less than 10 million years.

Active cryo-geophysical processes likely responsible for resurfacing.

Abstract

Data from the New Horizons mission to Pluto show no craters on Sputnik Planum down to the detection limit (2 km for low resolution data, 625 m for high resolution data). The number of small Kuiper Belt Objects that should be impacting Pluto is known to some degree from various astronomical surveys. We combine these geological and telescopic observations to make an order of magnitude estimate that the surface age of Sputnik Planum must be less than 10 million years. This maximum surface age is surprisingly young and implies that this area of Pluto must be undergoing active resurfacing, presumably through some cryo-geophysical process. We discuss three possible resurfacing mechanisms and the implications of each one for Pluto's physical properties.