The Pluto system: Initial results from its exploration by New Horizons

TL;DR

The New Horizons mission provided initial detailed observations of Pluto and its moons, revealing diverse geology, active surface processes, and atmospheric characteristics that challenge existing models of small planet activity.

Contribution

First comprehensive dataset from New Horizons on Pluto's geology, atmosphere, and moons, offering new insights into small planet activity and evolution.

Findings

Diverse landforms and surface compositions on Pluto.

Active geological processes such as ice convection and glacial flow.

Complex atmospheric composition with haze and trace hydrocarbons.

Abstract

The Pluto system was recently explored by NASA's New Horizons spacecraft, making closest approach on 14 July 2015. Pluto's surface displays diverse landforms, terrain ages, albedos, colors, and composition gradients. Evidence is found for a water-ice crust, geologically young surface units, surface ice convection, wind streaks, volatile transport, and glacial flow. Pluto's atmosphere is highly extended, with trace hydrocarbons, a global haze layer, and a surface pressure near 10 microbars. Pluto's diverse surface geology and long-term activity raise fundamental questions about how small planets remain active many billions of years after formation. Pluto's large moon Charon displays tectonics and evidence for a heterogeneous crustal composition, its north pole displays puzzling dark terrain. Small satellites Hydra and Nix have higher albedos than expected.