John V. Martonchik received the B.S. degree in physics from Case Institute of Technology in 1964 and the Ph.D. degree in astronomy from the University of Texas at Austin in 1974. He joined JPL in 1972 and currently holds the position of Research Scientist. His experiences include telescopic and spacecraft observations of planetary atmospheres, laboratory and theoretical studies of the optical properties of gaseous, liquid, and solid materials, and development and implementation of one- and three-dimensional radiative transfer and line-by-line spectroscopy algorithms for studies of planetary atmospheres and Earth tropospheric remote sensing. He has been a Co-Investigator in several NASA programs and is the Algorithm Scientist for aerosol and surface retrievals on MISR.