THE COMPOSITION OF THE MARTIAN SURFACE,

Abstract

It is generally believed that the desert areas of Mars are composed of limonite. This belief, which is based upon polarimetric, spectrometric, color, and albedo measurements, is in conflict with geologic reasoning. An examination of the evidence for limonite on Mars shows that the spectrometric measurements are most convincing. Laboratory experiments demonstrate, however, that the infrared emission spectra of minerals depend in part on grain size. Finely powdered minerals have infrared emission characteristic of a greybody, and yield very little spectral information. Thus, the Martian surface materials could be composed primarily of fine-grained silicates, or of coarse-grained silicates coated with finely divided limonite, without their presence being revealed spectrometrically. (Author)

Document Details

Document Type
Technical Report
Publication Date
Apr 01, 1965
Accession Number
AD0630076

Entities

People

  • John W. Salisbury
  • Roger A. Van Tassel

Organizations

  • Air Force Cambridge Research Laboratories

Tags

DTIC Thesaurus Topics

  • Buildings And Structures
  • Emission
  • Emission Spectra
  • Grain Size
  • Materials
  • Measurement
  • Minerals
  • Reasoning
  • Research Facilities
  • Silicates
  • Spectra

Fields of Study

  • Geology

Readers

  • Aerosol Science/Aerosol Physics
  • Astronomy and Astrophysics.
  • Systems Analysis and Design