Surface ices and the atmospheric composition of pluto.

Science (Impact Factor: 31.03). 09/1993; 261(5122):745-8. DOI: 10.1126/science.261.5122.745
Source: PubMed

ABSTRACT Observations of the 1.4- to 2.4-micrometer spectrum of Pluto reveal absorptions of carbon monoxide and nitrogen ices and confirm the presence of solid methane. Frozen nitrogen is more abundant than the other two ices by a factor of about 50; gaseous nitrogen must therefore be the major atmospheric constituent. The absence of carbon dioxide absorptions is one of several differences between the spectra of Pluto and Triton in this region. Both worlds carry information about the composition of the solar nebula and the processes by which icy planetesimals formed.

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    ABSTRACT: In this interview, Dale Cruikshank (Fig. 1) explains how as an undergraduate at Iowa State University he was a summer student at Yerkes Observatory where he assisted Gerard Kuiper in work on his Photographic Lunar Atlas. Upon completing his degree, Dale went to graduate school at the University of Arizona with Kuiper where he worked on the IR spectroscopy of the lunar surface. After an eventful 1968 trip to Moscow via Prague, during which the Soviets invaded Czechoslovakia, Dale assumed a postdoc position with Vasili Moroz at the Sternberg Astronomical Institute and more observational IR astronomy. Upon returning to the United States and after a year at Arizona, Dale assumed a position at the University of Hawai'i that he held for 17 years. During this period Dale worked with others on thermal infrared determinations of the albedos of small bodies beyond the asteroid Main Belt, leading to the recognition that low-albedo material is prevalent in the outer solar system that made the first report of complex organic solids on a planetary body (Saturn's satellite Iapetus). After moving to Ames Research Center, where he works currently, he continued this work and became involved in many outer solar system missions. Dale has served the community through his involvement in developing national policies for science-driven planetary exploration, being chair of the DPS 1990-1991 and secretary/treasurer for 1982-1985. He served as president of Commission 16 (Physics of Planets) of the IAU (2001-2003). He received the Kuiper prize in 2006.
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