Fall 2013 Department News

Two New Associate Professors Join LPL

LPL is excited to welcome two new faculty members starting Fall 2013—Drs. Travis Barman and Walt Harris both joined the LPL faculty as associate professors. Travis and Walt bring diverse and unique strengths to LPL and we look forward to many productive collaborations.

Travis Barman moved to Tucson from Flagstaff, where he worked as an astronomer at Lowell Observatory for seven years. Prior to Lowell, he was a post-doctoral fellow at the University of California, Los Angeles, and at Wichita State University. Travis received his Ph.D. at the University of Georgia. Travis’ research primarily involves numerical modeling of exoplanet atmospheres. These models guide a number of observational programs to study various classes of exoplanets, from super-Earths to massive young planets. By comparing theoretical model spectra to real photometric and spectroscopic observations, a variety of planet properties can be deduced. Atmospheric structure (horizontal and vertical run of temperature and pressure), surface gravities, chemical composition, and global wind patterns are a few examples of the kinds of planet properties we seek through model observation comparisons. Travis is also heavily involved in a ground-based survey to directly image young exoplanets using the Gemini Planet Imager (GPI). GPI is an extreme adaptive optics instrument being commissioned on Gemini-South this fall and, over the next several years, will be used to discover many young planetary systems. These discoveries will reveal new insights into planet evolution.

Walt Harris is an experimental planetary scientist with an interest in comets and the intersection between the space environment and the atmospheres of the planets and their satellites. He comes to LPL after serving for the past 6 years on the faculty of the University of California, Davis. Walt began his career at the Space Physics Research Lab at the University of Michigan where he earned his Ph.D. constructing and flying sounding rocket borne ultraviolet spectrometer to study the Jovian aurora. After graduating, he moved to the University of Wisconsin Space Astronomy Lab to work with the ultraviolet polarization group on a series of sounding rocket experiments, including two flights as principle investigator. While at Wisconsin, his research focus shifted toward ground and space based observations of comet atmospheres, and he began a collaboration with the space physics interferometry group centered on the development of all-reflective spatial heterodyne spectrometers. These areas now reflect the core of his research. Walt's interest in comets is centered on the photochemical evolution of volatiles liberated from the nucleus with an emphasis on identifying compositional variations with time and active region. He uses a combination of existing custom-built instruments for these studies. He also has active programs to develop heterodyne spectrometers, which are compact remote sensors capable of delivering wide field high resolution spectroscopy of extended objects, for use at ground based telescopes and a variety space platforms. His current projects in this area include a prototype broadband instrument under construction at the Lick Observatory and an ultraviolet sounding rocket experiment to study the interplanetary medium.