Europlanet Science Congress 2022
Palacio de Congresos de Granada, Spain
18 – 23 September 2022
Europlanet Science Congress 2022
Palacio de Congresos de Granada, Spain
18 September – 23 September 2022
EPSC Abstracts
Vol. 16, EPSC2022-1196, 2022, updated on 23 Sep 2022
Europlanet Science Congress 2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.

Discovering the Surface Composition of TNOs (DiSCo-TNOs) with the James Webb Space Telescope

Mario De Pra1, Noemi Pinilla-Alonso1, Ana Carolina Souza Feliciano1, Charles Schambeau1, Brittany Harvison1, Josh Emery2, Dale Cruikshank3, Yvonne Pendleton3, Bryan Holler4, John Stansberry4, Vania Lorenzi5, Thomas Muller6, Aurélie Guilbert-Lepoutre7, Nuno Peixinho8, Michele Bannister9, and Rosario Brunetto10
Mario De Pra et al.
  • 1University of Central Florida, Florida Space Institute, Orlando, United States of America (
  • 2Northern Arizona University
  • 3NASA Ames Research Center
  • 4Space Telescope Science Institute
  • 5Fundación Galileo Galilei - INAF
  • 6CNRS/Laboratoire de Géologie de Lyon
  • 7University of Canterbury
  • 8University of Coimbra
  • 9Max-Planck-Institut für extraterrestrische Physik
  • 10Institut d'Astrophysique Spatiale

The discovery of trans-Neptunian objects (TNOs) marked an important milestone in the understanding of the outer Solar System. Due to their environmental conditions, these objects could preserve the most pristine materials that were present on the protoplanetary disk. Studies focused on understanding TNOs physical and dynamical properties can be used to probe planetary formation processes and the subsequent solar system dynamical evolution that followed the formation era.

Nowadays, above 3,000 TNOs have been detected, including four large ones that receive the official designation of dwarf-planets. Analysis of TNOs revealed a compositionally and dynamically diverse population. However, despite all the progress in the last decades, much is still unknown about the composition of the TNOs.

The recently launched James Webb Space Telescope (launched on December 25, 2021) will provide a powerful tool to investigate the TNOs surface composition, where all prior instrumentation has fallen short. The NIRSpec instrument onboard JWST will provide high-quality data that will surpass the quality of the data available by orders of magnitude. DiSCo-TNOs, lead by the Florida Space Institute, is the only large program approved by JWST for the study of the Solar System. With it, we aim to assess the relative ratio of water ice, complex organics, silicates, and volatiles on the surface of a large sample of TNOs. This information is vital to improving models of the formation of our Solar System and other planetary systems. In this talk we present the scope of the DiSCo program, and the tools that are being developed to extract the maximal information from the data. We pay special attention to the compositional modeling technique that uses an implementation of a nested sampling algorithm for Bayesian inference of the abundances and grain sizes distribution of the materials present on TNOs surfaces.


How to cite: De Pra, M., Pinilla-Alonso, N., Souza Feliciano, A. C., Schambeau, C., Harvison, B., Emery, J., Cruikshank, D., Pendleton, Y., Holler, B., Stansberry, J., Lorenzi, V., Muller, T., Guilbert-Lepoutre, A., Peixinho, N., Bannister, M., and Brunetto, R.: Discovering the Surface Composition of TNOs (DiSCo-TNOs) with the James Webb Space Telescope, Europlanet Science Congress 2022, Granada, Spain, 18–23 Sep 2022, EPSC2022-1196,, 2022.

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