Open AccessVariations on solar condensation: Sources of interstellar dust nuclei
Author(s) -
Ebel Denton S.
Publication year - 2000
Publication title -
journal of geophysical research: space physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/1999ja900192
Subject(s) - interstellar medium , cosmic dust , physics , astrophysics , presolar grains , condensation , interplanetary dust cloud , refractory (planetary science) , astrochemistry , metal , outflow , heliosphere , solar wind , solar system , astrobiology , nucleosynthesis , materials science , galaxy , supernova , plasma , thermodynamics , meteorology , metallurgy , quantum mechanics
Some portion of the interstellar dust entering the heliosphere is a refractory (Ca‐Al‐Ti‐Mg‐Si‐Fe‐Ni‐Cr‐Co‐rich) component either condensed at high temperature from stellar outflows or formed in the interstellar medium (ISM). Condensation sequences for T >1100 K, assuming chemical equilibrium, are calculated for stellar outflow gas having (1) solar composition at various P tot ; (2) compositions approaching C/O=0.9, otherwise solar; (3) metallicities reduced by Z/Z o =0.10; and (4) metallicities enhanced by added dust components. Calculated depletions are relatively insensitive to these excursions from the canonical “cosmic” abundances. The intragroup similarities of depletions observed for the element groups (Ca‐Ti), (Fe‐Ni‐Cr‐Co), and (Mg‐Si) reflect the dominant mineralogy calculated for Stardust: Ti‐ and Ca‐aluminate phases, metal alloy, and Mg 2 SiO 4 (Mg‐olivine). This result suggests that the bulk of the refractory component of ISM dust was condensed in stellar environments.