Interpretations of optical observations of Mercury and the moon

Optical, thermal and radar remote-sensing measurements indicate that Mercury is covered with a relatively thick layer of soil similar in texture and thickness to lunar regolith. Photometric limb profiles measured by Mariner 10 imply that the small-scale slopes on Mercury are about half those on the moon, probably because of differing gravity. The differential photometric functions of Mercury and the moon have a latitudinal dependence which can be completely accounted for by shadowing in craters. The lack of polar darkening on Mercury in spite of the presence of a magnetic field implies that the dominant soil-darkening process on Mercury, and by extension, on the moon is not dependent on the solar wind, but probably is deposition of material evaporated by meteorite impacts. Recent measurements of Mercury's spectral reflectivity in the IR and vacuum UV are both consistent with the surface rocks of Mercury being lower in FeO than those of the moon. Based on laboratory experiments the average FeO content on the surface of Mercury is estimated to be between 3 and 6%.

[1]  D. Morrison Thermophysics of the planet Mercury , 1970 .

[2]  M E Davies,et al.  Mercury's Surface: Preliminary Description and Interpretation from Mariner 10 Pictures , 1974, Science.

[3]  T. Johnson,et al.  Soil maturity and planetary regoliths: the Moon, Mercury, and the asteroids. , 1977 .

[4]  T. McCord,et al.  Mercury: Surface Composition from the Reflection Spectrum , 1972, Science.

[5]  D. B. Nash,et al.  Spectral reflectance and albedo of Apollo 11 lunar samples - Effects of irradiation and vitrification and comparison with telescopic observations , 1970 .

[6]  B. Hapke A THEORETICAL PHOTOMETRIC FUNCTION FOR THE LUNAR SURFACE , 1963 .

[7]  N. Ness,et al.  The magnetic field of Mercury, 1 , 1975 .

[8]  F. Low,et al.  Infrared orbital mapping of lunar features , 1975 .

[9]  Lionel Wilson,et al.  Photometric observations of Mercury from Mariner 10 , 1975 .

[10]  P. Price,et al.  Electron microscopy of irradiation effects in space. , 1975, Science.

[11]  G. Wehner Sputtering Effects on the Moon's Surface , 1961 .

[12]  M. Minnaert Photometry of the Moon , 1961 .

[13]  A. Broadfoot Ultraviolet spectrometry of the inner solar system from Mariner 10 , 1976 .

[14]  Faith Vilas,et al.  Mercury: Spectral reflectance measurements (0.33–1.06 μm) 1974/1975 , 1976 .

[15]  B. Hapke,et al.  PHOTOMETRIC STUDIES OF COMPLEX SURFACES, WITH APPLICATIONS TO THE MOON , 1963 .

[16]  Bruce Hapke,et al.  EFFECTS OF A SIMULATED SOLAR WIND ON THE PHOTOMETRIC PROPERTIES OF ROCKS AND POWDERS * , 1965 .

[17]  A. J. Cohen,et al.  Solar radiation effects on the optical properties of Apollo 11 samples , 1970 .

[18]  Radar Observations of Mercury. , 1971, Science.

[19]  Bruce Hapke,et al.  Effects of vapor-phase deposition processes on the optical, chemical, and magnetic properties OE the lunar regolith , 1975 .

[20]  R. Housley,et al.  Origin and characteristics of excess Fe metal in lunar glass welded aggregates , 1973 .

[21]  L. Grossman Condensation in the primitive solar nebula , 1972 .

[22]  A. Dollfus,et al.  Polarimetric properties of the lunar surface and its interpretation. Part 3: Apollo 11 and Apollo 12 lunar samples , 1971 .

[23]  A. Lyle Broadfoot,et al.  The extreme ultraviolet albedos of the planet Mercury and of the Moon , 1977 .

[24]  B. Hapke,et al.  Lunar Soil: Iron and Titanium Bands in the Glass Fraction , 1977, Science.

[25]  B. Hapke Darkening of silicate rock powders by solar wind sputtering , 1973 .

[26]  R. Baron,et al.  Auger analysis of the lunar soil - Study of processes which change the surface chemistry and albedo , 1975 .

[27]  G. Siscoe,et al.  Variations in the solar wind stand‐off distance at Mercury , 1975 .

[28]  G. Neugebauer,et al.  Preliminary Infrared Radiometry of the Night Side of Mercury from Mariner 10 , 1974, Science.

[29]  JOHN S. Lewis Metal/silicate fractionation in the solar system , 1972 .

[30]  G. Thomas,et al.  Mercury's helium exosphere , 1975 .

[31]  B. Hapke An Improved Theoretical Lunar Photometric Function. , 1966 .

[32]  Audouin Dollfus,et al.  Optical polarimetry of planet mercury , 1974 .

[33]  G. Pettengill A review of radar studies of planetary surfaces , 1965 .