A Pluto-like radius and a high albedo for the dwarf planet Eris from an occultation - Sorbonne Université
Journal Articles Nature Year : 2011

A Pluto-like radius and a high albedo for the dwarf planet Eris from an occultation

R. Duffard
R. Behrend
  • Function : Author
A. Castro
I. de La Cueva
  • Function : Author
G. Muler
  • Function : Author
I. A. Steele
  • Function : Author
W. Reis
  • Function : Author

Abstract

The dwarf planet Eris is a trans-Neptunian object with an orbital eccentricity of 0.44, an inclination of 44 degrees and a surface composition very similar to that of Pluto. It resides at present at 95.7 astronomical units (1AU is the Earth-Sun distance) from Earth, near its aphelion and more than three times farther than Pluto. Owing to this great distance, measuring its size or detecting a putative atmosphere is difficult. Here we report the observation of a multi-chord stellar occultation by Eris on 6 November 2010 UT. The event is consistent with a spherical shape for Eris, with radius 1,163+/-6kilometres, density 2.52+/-0.05 grams per cm3 and a high visible geometric albedo, . No nitrogen, argon or methane atmospheres are detected with surface pressure larger than ~1nanobar, about 10,000 times more tenuous than Pluto's present atmosphere. As Pluto's radius is estimated to be between 1,150 and 1,200 kilometres, Eris appears as a Pluto twin, with a bright surface possibly caused by a collapsed atmosphere, owing to its cold environment. We anticipate that this atmosphere may periodically sublimate as Eris approaches its perihelion, at 37.8 astronomical units from the Sun.
Fichier principal
Vignette du fichier
Eris_letter.pdf (243 Ko) Télécharger le fichier
Eris_SI.pdf (406.29 Ko) Télécharger le fichier
Origin Files produced by the author(s)
Origin Files produced by the author(s)
Loading...

Dates and versions

hal-00637720 , version 1 (02-11-2011)

Identifiers

Cite

Bruno Sicardy, J. L. Ortiz, M. Assafin, E. Jehin, A. Maury, et al.. A Pluto-like radius and a high albedo for the dwarf planet Eris from an occultation. Nature, 2011, 478, pp.493-496. ⟨10.1038/NATURE10550⟩. ⟨hal-00637720⟩
483 View
1974 Download

Altmetric

Share

More