Nuclear Seminar

Radiation Chemistry in Cosmic Ices:
Observational Evidence and Predictions

Dr. Marla Moore
NASA Goddard Space Flight Center

Monday, May 16, 2005   4:00 p.m.   NSH 124
(Refreshments served prior to seminar in NSH 124)

Ices are known to exist in many regions of the universe: in cold interstellar dark clouds, comets, planetary rings, and on the surface of Pluto, many satellites, and several Kuiper Belt objects. Because these ices are subjected to radiation processing by keV-MeV ions and UV photons, their chemical and physical properties evolve over time. A review of known cosmic ices and some of the observed infrared signatures of these ices that indicate chemical changes, driven by radiation processing, will be presented. A few examples of our laboratory simulation experiments will demonstrate formation of complex molecules by radiation processing from simple starting ice mixtures. The over all theme of the talk will be to show the relevance of our laboratory results to astrobiology.