Argon solar system

The Zag meteorite fell in the western Sahara of Morocco in August 1998. This meteorite was unusual in that it contained small crystals of halite (table salt), which experts believe formed by the evaporation of brine (salt water). It is one of the few indications that liquid water, which is essential for the development of life, may have existed in the early solar system. The halite crystals in the meteorite had a remarkably high abundance of 128Xe, a decay product of a short-lived iodine isotope that has long been absent from the solar system. Scientists believe that the iodine existed when the halite crystals formed. The xenon formed when this iodine decayed. For this reason, the Zag meteorite is believed to be one of the oldest artifacts in the solar system. In this lab, you will use potassium-argon radiochemical dating to estimate the age of the Zag meteorite and the solar system. 

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. 

With the exception of some early potassium-argon ages of nearly 5 Ga, and which are believed to be analytical artifacts, aU high quality radio-metric ages of CAIs are no older than 4.56-4.57 Ga. This observation suggests that whole CAIs are not themselves presolar objects, although it does not rule out the possibility that presolar CAI precursors were reprocessed (melted or otherwise completely recrystallized) in the earliest solar system. For more on CAI chronology, see Chapter 1.16. 

Hunten DM, Pepin RO, Owen TC (1988) Planetary Atmospheres. In Meteorites and the Early Solar System. Kerridge JF, Matthews MS (eds) University of Arizona Press, Tucson, Arizona, p 565-591 Hunten DM, Donahue TM, Walker JCG, Kasting JF (1989) Escape of atmospheres and loss of water. In Origin and Evolution of Planetary and Satellite Atmospheres. Atreya SK, Pollack JB, Matthews MS (eds) University of Arizona Press, Tucson, Arizona, p 386-422 Hutchins KS, Jakosky BM (1996) Evolution of martian atmospheric argon Implications for sources of volatiles. J Geophys Res 101 14933-14949... 

Hutchins KS, Jakosky BM, Luhmarm JG (1997) Impact of a paleomagnetic field on sputtering loss of martian atmospheric argon and neon. J Geophys Res 102 9183-9189 Igarashi G (1995) Primitive Xe in the Earth. In Volatiles in the Earth and Solar System. Farley KA (ed). Am Inst Phys Coirf Proc 341 70-80... 

Solar systems, or direct diabolic intervention, the writer feels that the exothermic argument is so strong that he, hesitantly, must look for other explanations such as collective hypnosis. Anyhow, for Crookes living 100 years ago, there was still enough of a connection with pre-scientific ideas that he suspected a maturation of the meta-elements in minerals. By the way, this is one of the rare cases of older history being optimistic and newer ideas pessimistic with exception of nuclear physics directed by human beings, the only transmutation of elements on Earth is the irreversible and uninfluenced natural radioactivity of which the chains mranium 238 to lead 206, thorium 232 to lead 208, and the rare isotope potassium 40 to argon 40 (1 percent of the atmosphere) and calcium 40 have a perceptible influence on the heat balance of the crust. 

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