Hale, Matthew

While many asteroids may have previously been comet-like, even active comets are somewhat asteroid like. The traditional concept of comets as dirty snowballs has been modified by some authors to consider them to be more like frosty rocks, because they contain more rock than ice. The dust gas production rate from the spectacularly active comet Hale-Bopp exceeded its gas production rate by a factor of 5 (Jewitt and Matthews, 1999). In considering the water contents of comets, it is interesting to consider that some comets may have ice abundances similar to the bound water content of hydrated silicate-rich asteroids. At least in some cases, comets and asteroids might have similar capacities for carrying water to other solar system bodies. 

Jewitt D. and Matthews H. (1999) Particulate mass loss from comet Hale-Bopp. Aitron. J. 117, 1056-1062. 

Jewitt D., Senay M., and Matthews H. (1996) Observations of carbon monoxide in comet Hale-Bopp. Science 271, 1110-1113. 

David L. Dull,/Matthew Hale, Anne K. Hollander, Jane Rissler, and Carl Mazza... 

Systemic effects of acute inhalation exposure to generally unspecified levels of various zinc compounds in humans have been reported in several clinical case studies (Blanc et al. 1991 Brown 1988 Hjortso et al. 1988 Matarese and Matthews 1966 Vogelmeier et al. 1987). Case studies and experimental studies of systemic effects in humans following acute, intermediate, and chronic oral exposures are available (Anonymous 1983 Black et al. 1988 Brandao-Neto et al. 1990a Chandra 1984 Chobanian 1981 Hale et al. 1988 Hallbook and Lanner 1972 Hoffman et al. 1988 Hooper et al. 1980 Malo et al. 1990 Moore 1978 Patterson et al. 1985 Porter et al. 1977 Potter 1981 ... 

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