Mass Spectrometric Measurement of Martian Krypton and Xenon Isotopic Abundance

The Viking gas chromatograph mass spectrometer experiment provided significant data on the atmospheric composition at the surface of Mars, including measurements of several isotope ratios. However, the limited dynamic range of this mass spectrometer resulted in marginal measurements for the important Kr and Xe isotopic abundance. The Xe-129 to Xe-132 ratio was measured with an uncertainty of 70%, but none of the other isotope ratios for these species were obtained. Accurate measurement of the Xe and Kr isotopic abundance in this atmosphere provides an important data point in testing theories of planetary formation and atmospheric evolution. The measurement is also essential for a stringent test for the Martian origin of the SNC meteorites, since the Kr and Xe fractionation pattern seen in gas trapped in glassy nodules of an SNC (EETA 79001) is unlike any other known solar system resevoir. Current flight mass spectrometer designs combined with the new technology of a high-performance vacuum pumping system show promise for a substantial increase in gas throughput and the dynamic range required to accurately measure these trace species. Various aspects of this new technology are discussed

Intelligent Design: The Bridge Between Science and Theology (Book Review)

Reviewed Title: Intelligent Design: The Bridge Between Science and Theology, by William A. Dembski (Downers Grove, IL: InterVarsity Press, 1999). 312 pages. ISBN 0-830-815813

Reason in the Balance: The Case Against Naturalism in Science, Law, and Education (Book Review)

Reviewed Title: Reason in the Balance: The Case Against Naturalism in Science, Law, and Education, by Phillip E. Johnson (Downers Grove, Illinois: InterVarsity Press, 1995). 245 pages

Chromatographic, Spectroscopic and Mass Spectrometric Approaches for Exploring the Habitability of Mars in 2012 and Beyond with the Curiosity Rover

The Sample Analysis at Mars (SAM) suite of instruments on the Curiosity Rover of Mars Science Laboratory Mission is designed to provide chemical and isotopic analysis of organic and inorganic volatiles for both atmospheric and solid samples. The goals of the science investigation enabled by the gas chromatograph mass spectrometer and tunable laser spectrometer instruments of SAM are to work together with the other MSL investigations is to quantitatively assess habitability through a series of chemical and geological measurements. We describe the multi-column gas chromatograph system employed on SAM and the approach to extraction and analysis of organic compounds that might be preserved in ancient martian rocks

Student Use of Library Research Guides Following Library Instruction

Librarians often provide students who attend one-shot library instruction sessions with research guides they can refer to once class is over. These guides, whether in paper or electronic form, serve to remind the students of key points and resources addressed during the session. It is unclear, though, if and how students refer to these guides once leaving the classroom. This article reports on the results of two focus groups made up of students who attended a basic library instruction session as part of a survey art course. The students shared how they used a paper and electronic research guide, delivered via LibGuides, and what they would like research guides to contain. The article also suggests directions for further research on the topic

Darwin\u27s Black Box: The Biochemical Challenge to Chemical Evolution (Book Review)

Reviewed Title: Darwin\u27s Black Box: The Biochemical Challenge to Chemical Evolution by Mike Behe, 1996 Free Press (A division of Simon and Schuster) 307 pp