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Project Progress

Mr. William Anderson is a graduate student at the Catholic University of America, pursuing his PhD under the mentorship of Co-I DiSanti. His thesis topic is a comparative study of the chemistry of oxidized carbon among comets belonging to two principal dynamical reservoirs: Long-period comets, coming from the Oort cloud, and short-period comets that are in dynamical resonance with the Sun and Jupiter (the so-called “Jupiter Family” comets, JFCs). The JFCs are thought to come primarily from the scattered Kuiper disk population of comets.

Mr. Anderson is currently finalizing his work on comet T7 LINEAR. A paper is in preparation that will report the oxidized carbon chemistry from data obtained on two observing runs of several days each that are separated by several weeks. This will search for changes in abundances for CO, H₂CO, and CH₃OH relative to H₂O, both day-to-day, and between early and late May 2004 (“seasonal” changes). Mr. Anderson participated in the latter run.

Anderson and DiSanti recently returned from observing comet 73P/Schwassmann-Wachmann 3 in May 2006. Because of the faint nature of this comet, the observations targeted simultaneous measurements of CO and H₂O, with the goal of detecting (or obtaining a stringent upper limit to the abundance of) CO in this comet. Water emission was definitively detected, and given the large amount of time spent on the comet we expect to constrain the CO abundance to about one percent or less that of H₂O. Once finalized, we expect to publish the result as a note — although various parent molecules have been measured in S-W 3 by us (and others), no one has successfully measured CO in this comet.