Astronomy and Astrophysics – Astronomy
Scientific paper
Dec 1997
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1997arcn.rept..365b&link_type=abstract
Analysis of Returned Comet Nucleus Samples, Proceedings of a Workshop held at Milpitas, California, 16-18 January, 1989. Compil
Astronomy and Astrophysics
Astronomy
Comet Nuclei, Comets, Mass Spectroscopy, Micrometeoroids, Particle Size Distribution, Cosmic Dust, Isotope Ratios, Astronomical Models, Ion Probes, Rare Gases, Heavy Elements, Halley''S Comet
Scientific paper
Comets are still believed to be a conglomerate of ices and meteoritic dust in a ratio of about 5:1 (if we take the ratio ices/dust to be equal to the ratio gas/dust). When Whipple proposed his "dirty snowball" model in 1950 he envisaged a single, well consolidated body; recent refinements are the icy-glue model for the cometary nucleus of Houpis and Gombosi (1986) or the "primordial rubble pile" of Weissman (1986). These refinements appear to pertain essentially to the macroscopic structure of the nucleus on the scale of tens of centimeters to hundreds of meters, however, so they need not concern us in the present context, since we are interested in the structure on a much smaller scale. What we should like to know is the size distribution of non-gaseous matter ("gaseous" at elevated temperatures like room temperature) which we may expect in a kg-sized sample. The most recent and most comprehensive data available on this topic are those obtained for comet Halley which may or may not be typical of comets - but then we do not know, of course, how "typical" the first returned cometary sample will be either. The understanding was that this presentation should consist of two parts, one about what one may hope to learn from the isotopic analysis in the laboratory of cometary matter, and a second part on whether present-day analytical methods are adequate to reach these goals, where improvements are required and what needs to be developed in order to optimize the scientific return. The understanding was, furthermore, that I should report on isotopics and the analysis of heavy elements and noble gases by conventional mass spectrometry, but that I should neither concern myself with light elements like H, C, O and N, nor should I deal with the potential of ion probes.
No associations
LandOfFree
On the Isotope Analysis of Cometary Dust does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with On the Isotope Analysis of Cometary Dust, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and On the Isotope Analysis of Cometary Dust will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1181035