NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Condensation time of the solar nebula from extinct I-129 in primitive meteoritesMineral separates from five carbonaceous chondrites were dated by extinct 16 million year I-129, in an attempt to establish the condensation time of the solar nebula. Two Fe3O4 or Fe3O4-FeS samples from the Murchison and Orgueil meteorites are older than any other material dated thus far, and apparently formed within 200,000 years of each other. The great age, close isochronism, and primitive nature of the samples suggest that the event recorded was the condensation stage of the solar nebula. It provides a suitable zero point for the chronology of the early solar system. The I-129/I-127 ratio during condensation of the nebula was (1.46 plus or minus 0.04) times 0.0001. The recrystallized C4 chondrite Karoonda began to retain Xe-129 1.8 plus or minus 0.5 million years after the above event. This short cooling time implies rapid accretion (not exceeding 1 million years) and a shallow origin (not exceeding 10 km) below the surface of its parent body.-
Document ID
19760038830
Document Type
Reprint (Version printed in journal)
Authors
Lewis, R. S. (Chicago Univ. Chicago, IL, United States)
Anders, E. (Chicago, University Chicago, Ill., United States)
Date Acquired
August 8, 2013
Publication Date
January 1, 1975
Publication Information
Publication: National Academy of Sciences
Subject Category
LUNAR AND PLANETARY EXPLORATION
Funding Number(s)
CONTRACT_GRANT: NGL-14-001-010
Distribution Limits
Public
Copyright
Other