Back

Title
  • Pure iron grains are rare in the universe
Creator

Kimura, Yuki

Tanaka, Kyoko K.

Nozawa, Takaya

Takeuchi, Shinsuke

Inatomi, Yuko

Rights
    • https://creativecommons.org/licenses/by-nc/4.0/
Description
Other
  • The abundant forms in which the major elements in the universe exist have been determined from numerous astronomical observations and meteoritic analyses. Iron (Fe) is an exception, in that only depletion of gaseous Fe has been detected in the interstellar medium, suggesting that Fe is condensed into a solid, possibly the astronomically invisible metal. To determine the primary form of Fe, we replicated the formation of Fe grains in gaseous ejecta of evolved stars by means of microgravity experiments. We found that the sticking probability for the formation of Fe grains is extremely small; only a few atoms will stick per hundred thousand collisions so that homogeneous nucleation of metallic Fe grains is highly ineffective, even in the Fe-rich ejecta of type Ia supernovae. This implies that most Fe is locked up as grains of Fe compounds or as impurities accreted onto other grains in the interstellar medium.
PublisherThe American Association for the Advancement of Science(AAAS)
Date Issued 2017-01
Languageeng
NIItypejournal article
VersiontypeVoR
Identifier URI http://hdl.handle.net/2115/64900
Relation
  • isIdenticalTo DOI https://doi.org/10.1126/sciadv.1601992
Journal
    • ISSN 2375-2548
    • Science advances
    3(1), e1601992
File
Oaidate2018-06-15T00:42:41Z