Surface compositions and colors of Pluto, its system of moons, and 2014 MU69
Abstract
The trans-neptunian population is extremely diverse, with bodies ranging from geologically-active, atmosphere-bearing, volatile-dominated dwarf planets to small primitive planetesimals lacking abundant surface volatile ices (e.g., methane, nitrogen, carbon monoxide)---what we think of as the building blocks of planets. Our understanding of the Kuiper Belt has been limited by the challenges of acquiring high-quality spectroscopy for midsize and small trans-neptunian objects and composition maps of large dwarf planets. NASA's New Horizons mission represents a breakthrough in our understanding of the trans-neptunian population providing a detailed portrait of objects with very different size scales: the 2400-km-diameter dwarf planet Pluto, the midsize ~1200-km-diameter body Charon, and the much smaller Pluto's satellites (e.g., Nix and Hydra) and (486958) 2014 MU69 (hereafter MU69), the latter with an 18 km equivalent spherical diameter. This is the result of two successful flybys: that of Pluto and its moons on July 14th, 2015 (Stern, S. A., Bagenal, F., Ennico, K., et al. 2015, Science, 350, aad1815), and that of MU69 on January 1st, 2019 (Stern, S. A., Weaver, H. A., Spencer, J. R., et al. 2019, Science, 364, aaw9771). We will present an overview of the color and composition of these very diverse bodies in terms of size, evolutionary stage, and dynamical class in the broad context of the physical and chemical properties of other trans-neptunian objects. Comparing and contrasting these objects will shed light on the mechanisms at play during the epoch of planet formation in the Third Zone of the Solar System.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFM.P42C..04P
- Keywords:
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- 6040 Origin and evolution;
- PLANETARY SCIENCES: COMETS AND SMALL BODIES;
- 6224 Kuiper belt objects;
- PLANETARY SCIENCES: SOLAR SYSTEM OBJECTS;
- 6270 Pluto and satellites;
- PLANETARY SCIENCES: SOLAR SYSTEM OBJECTS;
- 5455 Origin and evolution;
- PLANETARY SCIENCES: SOLID SURFACE PLANETS