Ellipsoidal geometry in asteroid thermal models: The standard radiometric model

Research output: Contribution to journalArticle

28 Citations (Scopus)

Abstract

This paper reports results of the incorporation of ellipsoidal geometry into the standard radiometric model for asteroids. For small departures from spherical shape the standard model using spherical geometry predicts fluxes in good agreement with ellipsoidal models. Large departures from spherical shape, however, can produce substantial differences in the calculated flux depending on the subsolar temperature and the wavelength of interest. The results derived here suggest that radiometric measurements of highly nonspherical, low-obliquity asteroids interpreted with spherical models result in systematically smaller diameter and higher albedos. In addition, non-spherical shape can also result in a systematic difference in the diameter of a particular asteroid derived from separate 10- and 20-μm flux measurements interpreted with spherical models. Thermal-infrared diurnal lightcurves calculated for ellipsoids have amplitudes that depend on wavelength as well as projected area, and phase curves calculated for ellipsoids are indistinguishable from those calculated for spheres.

Original languageEnglish (US)
Pages (from-to)53-63
Number of pages11
JournalIcarus
Volume64
Issue number1
DOIs
StatePublished - 1985
Externally publishedYes

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asteroids
asteroid
geometry
ellipsoids
wavelength
albedo
wavelengths
obliquity
flux measurement
curves
temperature

ASJC Scopus subject areas

  • Space and Planetary Science
  • Astronomy and Astrophysics

Cite this

Ellipsoidal geometry in asteroid thermal models : The standard radiometric model. / Brown, Robert H.

In: Icarus, Vol. 64, No. 1, 1985, p. 53-63.

Research output: Contribution to journalArticle

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