TNOs are cool: a survey of the trans-Neptunian region: III. thermophysical properties of 90482 Orcus and 136472 Makemake [Letter to the editor]

Lim, T. L. and Horner, J. (2010) TNOs are cool: a survey of the trans-Neptunian region: III. thermophysical properties of 90482 Orcus and 136472 Makemake [Letter to the editor]. Astronomy and Astrophysics, 518 (2). L148. ISSN 0004-6361

Text (Published Version)

Download (136Kb) | Preview


Context. The goal of the Herschel open time programme 'TNOs are Cool!' is to derive the physical and thermal properties for a large sample of Centaurs, and trans-Neptunian objects (TNOs), including resonant, classical, detached and scattered disk objects.
Aims: Based on observations of two targets we tried (i) to optimise the SPIRE observing technique for faint (close to the background confusion noise), slowly moving targets; (ii) to test different thermal model techniques; (iii) to determine radiometric diameter and albedo values; (iv) to compare with Spitzer results whenever possible.
Methods: We obtained SPIRE photometry on two targets and PACS photometry on one of the targets.
Results: We present results for the two targets, (90482) Orcus and (136472) Makemake, observed with SPIRE and for one of those targets, Makemake, observed with PACS. We adopt pV = 0.27 and D = 850 km as our best estimate of the albedo and diameter of Orcus using single terrain models. With two-terrain models for Makemake, the bright terrain is fitted by, 0.78 < pV < 0.90, and the dark terrain 0.02 < pV < 0.12, giving 1360 < D < 1480 km.
Conclusions: A single terrain model was derived for Orcus through the SPIRE photometry combined with MIPS data. The Makemake data from MIPS, PACS and SPIRE combined are not compatible with a single terrain model, but can be modelled with a two-terrain fit. These science demonstration observations have shown that the scanning technique, which allows us to judge the influence of background structures, has proved to be a good basis for this key programme.
Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.

Statistics for USQ ePrint 25560
Statistics for this ePrint Item
Item Type: Article (Commonwealth Reporting Category C)
Refereed: Yes
Item Status: Live Archive
Additional Information: Copyright ESO 2010. This publication is copyright. It may be reproduced in whole or in part for the purposes of study, research, or review, but is subject to the inclusion of an acknowledgment of the source.
Faculty / Department / School: Historic - Faculty of Engineering and Surveying - No Department
Date Deposited: 23 Jul 2014 05:17
Last Modified: 16 Oct 2014 05:44
Uncontrolled Keywords: photometric techniques; Kuiper belt objects; 90482 Orcus; 136472 Makemake; infrared; submillimeter
Fields of Research : 02 Physical Sciences > 0203 Classical Physics > 020304 Thermodynamics and Statistical Physics
02 Physical Sciences > 0201 Astronomical and Space Sciences > 020110 Stellar Astronomy and Planetary Systems
02 Physical Sciences > 0201 Astronomical and Space Sciences > 020108 Planetary Science (excl. Extraterrestrial Geology)
Socio-Economic Objective: E Expanding Knowledge > 97 Expanding Knowledge > 970102 Expanding Knowledge in the Physical Sciences
Identification Number or DOI: 10.1051/0004-6361/201014701

Actions (login required)

View Item Archive Repository Staff Only