The Uranian satellites

Surface compositions and opposition brightness surges

Robert H. Brown, Dale P. Cruikshank

Research output: Contribution to journalArticle

62 Citations (Scopus)

Abstract

High-precision spectrophotometry at 5% resolution has been obtained for the Uranian satellites Ariel, Umbriel, Titania, and Oberon. These spectra cover the wavelength region 1.43-2.57 μm and represent a substantial improvement in precision or wavelength coverage over previous studies. The presence of a spectrally dominant water-ice component in the surface of Ariel, Umbriel, Titania, and Oberon is confirmed. The 1.5- and 2.0-μm water absorption band depths and the continuum reflectance (as defined by the reflectance at 1.78 and 2.25 μm) indicate significant differences among the surface compositional properties of the four satellites. Comparisons of the new spectra to those of other solar system bodies, and to laboratory spectra of water ice of various degrees of purity, indicate that these satellites have a significant non-water-ice component on/in their surfaces. The lack of spectral absorptions at 5% resolution attributable to anything other than water ice suggests that the non-water-ice component is a roughly neutral reflector in the 1.5- to 2.5- μm region. The nature of the non-water-ice component cannot be uniquely determined from these data, but it is relatively dark and has spectral similarities to substances such as carbon black, the dark substance covering one face of Iapetus, or other neutral-color, low-reflectance materials. Finally, preliminary measurements of the near-infrared opposition brightness surges of Ariel, Titania, and Oberon show them to be among the largest in the solar system.

Original languageEnglish (US)
Pages (from-to)83-92
Number of pages10
JournalIcarus
Volume55
Issue number1
DOIs
StatePublished - 1983
Externally publishedYes

Fingerprint

satellite surfaces
Oberon
brightness
ice
Titania
Umbriel
Ariel
titanium
reflectance
solar system
Ariel satellites
water
Iapetus
wavelength
absorption spectra
spectrophotometry
black carbon
wavelengths
surface properties
reflectors

ASJC Scopus subject areas

  • Space and Planetary Science
  • Astronomy and Astrophysics

Cite this

The Uranian satellites : Surface compositions and opposition brightness surges. / Brown, Robert H.; Cruikshank, Dale P.

In: Icarus, Vol. 55, No. 1, 1983, p. 83-92.

Research output: Contribution to journalArticle

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