Planet Xenon

On the planet Xenon, there are massive trees. These trees produce many very large, hanging pods every four years. The pods grow gradually and depend for their development upon the copious rainfall that is found on Xenon. When the contents of the pods are ready for harvesting, their shells... 

Ott U (1993) Physical and isotopic properties of surviving interstellar carbon phases. In Protostars Planets III. Levy Hand Lunine JI (eds) University of Arizona Press, Tucson, p 883-902 Ott U (1996) Interstellar diamond xenon and timescales of supernova ejecta. Astrophys J 463 344-348 Ott U, Begemann F, Yang J, Epstein S (1988) S-process krypton of variable isotopic composition in the Murchison meteorite. Nature 332 700-702... 

The preservation of distinct mantle reservoirs over time in Mars and the limited degassing experienced by the Martian mantle after the initial period, as indicated by the almost quantitative retention of 244Pu-produced fission xenon, show that Mars has been a static planet with no mantle convection since very early in its history. 

In contrast to the terrestrial planets, the giant planets are massive enough to have captured and retained nebular gases directly. However, concentrations of argon, krypton, and xenon measured in Jupiter s atmosphere by the Galileo spacecraft are 2.5 times solar, which may imply that its atmosphere preferentially lost hydrogen and helium over the age of the solar system. 

Noble gases may provide a constraint on the source of water and other volatiles. The abundance pattern of noble gases in planetary atmospheres resembles that of chondrites, perhaps arguing against comets. However, there are some differences, especially in the abundance of xenon. Relative to solar system abundances, krypton is more depleted than xenon in chondrites, but in the planets, krypton and xenon are present in essentially solar relative abundances (Fig. 10.11). This observation has been used to support comets as the preferred source of volatiles (even though measurements of xenon and krypton in comets are lacking). A counter-argument is that the Ar/H20 ratio in comets (if the few available measurements are accurate and representative) limits the cometary addition of volatiles to the Earth to only about 1%. 

Lewis, R. S. Anders, E. 1989 Xenon HL in diamonds from the Allende meteorite x-composite nature. Lunar. Planet. Sci. XIX, 679-680. 

Marti, K. (1967) Isotopic composition of trapped krypton and xenon in chondrites. Earth Planet. Sci. Lett., 3, 243-8. 

Podosek, F. A., Bematowicz, T. I, Kramer, F. E. (1981a) Adsorption and excess fission xenon. Proc. Lunar Planet. Sci., 12B, 891-901. 

Heymann D. and Dziczkaniec M. (1979) Xenon from intermediate zones of supemovae. In Lunar Planet. Sci. X. The Lunar and Planetary Instimte, Houston (CD-ROM), pp. 1943-1959. 

For most of the chemical elements, the relative abundances of their stable isotopes in the Sun and solar nebula are well known, so that any departures from those values that may be found in meteorites and planetary materials can then be interpreted in terms of planet-forming processes. This is best illustrated for the noble gases neon, argon, krypton, and xenon. The solar isotopic abundances are known through laboratory mass-spectrometric analysis of solar wind extracted from lunar soils (Eberhardt et al., 1970) and gas-rich meteorites. Noble gases in other meteorites and in the atmospheres of Earth and Mars show many substantial differences from the solar composition, due to a variety of nonsolar processes, e.g., excesses of " Ar and... 

Krot A. N., Brearley A. J., Ulyanov A. J., Biryukov V. V., Swindle T. D., Keil K., Mittlefehldt D. W., Scott E. R. D., and Nakamura K. (1998d) Mineralogy, petrography, bulk chemical, iodine-xenon, and oxygen isotopic compositions of dark inclusions in the reduced CV3 chondrite Efremovka. Meteorit. Planet. Sci. 34, 67-89. 

Swindle T. (1998) Implications of iodine-xenon studies for the timing and location of secondary alteration. Meteorit. Planet Sci. 33, 1147-1156. 

Gilabert E., Lavielle B., Michel R., Leya L, Neumann S., and Herpers U. (2002) Production of krypton and xenon isotopes in thick stony and iron targets isotropically irradiated with 1600 MeV protons. Meteorit. Planet. Sci. 37, 951—976. 

Pepin R. O. (2000) On the isotopic composition of primordial xenon in terrestrial planet atmospheres. Space Sci. Rev. 92, 371-395. 

Marty B. (1989) Neon and xenon isotopes in MORB implications for the earth-atmosphere evolution. Earth Planet. Sci. Lett. 94, 45 -56. 

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