Published 2010 | Version v1
Journal article

``TNOs are cool'': A survey of the trans-Neptunian region. II. The thermal lightcurve of (136108) Haumea

Others:
Observatoire de Paris ; Université Paris sciences et lettres (PSL)
Konkoly Observatory, Research Center for Astronomy and Earth Sciences
Max-Planck-Institut für Extraterrestriche Physik (MPE)
Université Sorbonne Paris Cité (USPC)
Laboratoire d'Astrophysique de Marseille (LAM) ; Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)
Royal Society, Astrophysics Research Centre, Physics Building, Queen's University, Belfast, County Antrim
Instituto de Astrofisica de Andalucia, CSIC (IAA)
Deutsches Zentrum für Luft- und Raumfahrt (DLR)
Space Science and Technology Department, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxon UK
Observatoire de la Côte d'Azur (OCA) ; Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
Max-Planck-Institut für Sonnensystemforschung, Katlenburg-Lindau (MPS)
Steward Observatory, University of Arizona
Department of Physics and Astronomy, Northern Arizona University, Flagstaff
INAF-Osservatorio Astronomico di Roma (INAF-OAR)
European Southern Observatory (ESO)
Institut de Mécanique Céleste et de Calcul des Ephémérides (IMCCE) ; Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris ; Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)
Groupe Astrométrie et Planétologie (GAP) ; Institut de Mécanique Céleste et de Calcul des Ephémérides (IMCCE) ; Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris ; Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris ; Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)
Department of Physics and Astronomy, Durham University
European Space Astronomy Centre (ESAC) ; European Space Agency (ESA)
University of Bern (UBERN)

Description

Thermal emission from Kuiper belt object (136108) Haumea was measured with Herschel-PACS at 100 mum and 160 mum for almost a full rotation period. Observations clearly indicate a 100 mum thermal lightcurve with an amplitude of a factor of ~2, which is positively correlated with the optical lightcurve. This confirms that both are primarily due to shape effects. A 160 mum lightcurve is marginally detected. Radiometric fits of the mean Herschel- and Spitzer- fluxes indicate an equivalent diameter D ~ 1300 km and a geometric albedo pv ~ 0.70-0.75. These values agree with inferences from the optical lightcurve, supporting the hydrostatic equilibrium hypothesis. The large amplitude of the 100 mum lightcurve suggests that the object has a high projected a/b axis ratio (~1.3) and a low thermal inertia as well as possible variable infrared beaming. This may point to fine regolith on the surface, with a lunar-type photometric behavior. The quality of the thermal data is not sufficient to clearly detect the effects of a surface dark spot.

Abstract

International audience

Additional details

Created:
December 3, 2022
Modified:
November 29, 2023