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Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
The mass of dwarf planet Eris.
Michael E Brown1, Emily L Schaller
1Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, USA.
Science (New York, N.Y.)
|June 16, 2007
Summary
Researchers precisely measured the orbit of Dysnomia, a satellite of dwarf planet Eris. This allowed them to determine Eris
Area of Science:
- Astronomy and Planetary Science
- Trans-Neptunian Objects
- Dwarf Planet Characterization
Background:
- The dwarf planet Eris has a satellite, Dysnomia, but its orbital parameters and the system's total mass were previously unknown.
- Understanding these parameters is crucial for characterizing Eris and its formation history.
Purpose of the Study:
- To precisely determine the orbital parameters of Dysnomia around Eris.
- To calculate the mass of the Eris-Dysnomia system.
- To infer the formation mechanism of Dysnomia.
Main Methods:
- Utilized new observational data from the Keck Observatory and the Hubble Space Telescopes.
- Analyzed observations to determine Dysnomia's orbital radius and period.
- Applied orbital mechanics to calculate the system's mass.
Main Results:
- Dysnomia orbits Eris in a circular path with a radius of 37,350 +/- 140 km.
- The orbital period of Dysnomia around Eris is 15.774 +/- 0.002 days.
- The calculated mass of Eris is 1.67 x 10^22 +/- 0.02 x 10^22 kg, approximately 1.27 times the mass of Pluto.
Conclusions:
- The determined orbital parameters are consistent with Dysnomia forming from debris following a giant impact.
- The mass of Eris is now precisely constrained, aiding in comparative planetology within the outer solar system.
- This study refines our understanding of dwarf planet systems and their dynamical evolution.
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