Asteroid spectroscopy

Meteorites provide perhaps the best record of the chemical evolution of small bodies in the Solar System, and this record is supplemented by asteroidal spectroscopy. Meteorites show progressive degrees of thermal processing on their parent asteroids, from primitive carbonaceous chondrites that contain percent-level quantities of water, through ordinary chondrites that show a wide range of degree of thermal metamorphism, to the achondrites that have been melted and differentiated. 

Potassium and thorium, which normally occur in minor or trace abundances, have been determined in surface materials on the Moon, Mars, and an asteroid by gamma-ray spectroscopy from orbiting spacecraft. 

Table 11.2 Analyses of asteroids by spacecraft X-ray diffraction and gamma-ray spectroscopy ...

Pieters, . M. and McFadden, L. A. (1994) Meteorite and asteroid reflectance spectroscopy clues to early solar system processes. Annual Reviews of Earth and Planetary Sciences, 22, 457-497. 

Before the advent of the Apollo and Luna missions which retrieved samples from the Moon s surface, meteorites provided the only source of extraterrestrial materials and raised questions about their sources from parent bodies such as asteroids. Visible to near-infrared reflectance spectroscopy, therefore, has been applied extensively to laboratory investigations of meteorites and to remote-sensed measurements of many asteroids (Gaffey, 1976 Gaffey and McCord, 1978 McFadden et al., 1982,1984 Bell and Keil, 1988). 

Gaffey, M. J. McCord, T. B. (1978) Asteroid surface materials Mineralogical characterization from reflectance spectroscopy. Space Sci. Rev., 21,555-628. 

McFadden, L. A., Gaffey, M. J., Takeda, H., Jackowski, T. L. Reed, K. L. (1982) Reflectance spectroscopy of diogenite meteorite types from Antarctica and their relationship to asteroids. Mem. Nat. Inst. Planet. Res., 25,188-206. 

Moroz, L.V. Arnold, G. Korochantsev, A.V. Wasch, R. Natural solid bitumens as possible analogs for cometary and asteroid organics 1. Reflectance spectroscopy of pure bitumens. Icarus 1998, 134, 253-268. 

Figure 1. Colonisation of Nocardia asteroides (15 min) on peroxidised commercial degradable PE (EPI TDPA ) by epifluorescence spectroscopy (Reproduced with kind permission of A-M.Delort and co-workers, Clermont-Ferrand, University). ...

The theories of radiative transfer, molecular spectroscopy, and atmospheric physics are first combined to show how it is possible to calculate the infrared spectra of model planetary atmospheres. Next the authors describe the instrumental techniques, in order to assess the effect of real instruments on the measurement of the emerging radiation field. Finally, techniques that allow the retrieval of atmospheric and surface parameters from observations are examined. There are plenty of examples from ground-based and space observations that demonstrate the methods of finding temperatures, gas compositions, and certain parameters of the solid surface. All planets from Mercury to Pluto, many of their satellites, asteroids, and comets are discussed. 

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