コンドルル形成のための新しい天体物理学的設定
A N Krot1, A Meibom, S S Russell
1Hawai'i Institute of Geophysics and Planetology (HIGP), School of Ocean and Earth Science and Technology (SOEST), University of Hawai'i at Manoa, Honolulu, HI 96822, USA. sasha@pgd.hawaii.edu
Science (New York, N.Y.)
|March 7, 2001
まとめ
隕石のコンドルールは,蒸発した塵で高温 (≥1500 K) で形成される極端な太陽星雲の条件を明らかにします. これは,コンドルル形成の伝統的なモデルに挑戦しています.
科学分野:
- * 惑星科学 (惑星科学)
- * アストロケミストリー
- * 隕石のようなもの
背景:
- *ホンドルルは隕石の重要な構成要素であり,太陽系の初期状態についての洞察を提供します.
- *従来型のモデルは,短時間,局所的な加熱イベントを通じてコンドルールの形成を提案しています.
- * コンドルール形成の正確な熱的・化学的な環境については,まだ議論が続いている.
研究 の 目的:
- * 金属が豊富な隕石 (ハマダ・アル・ハムラ237とQUE 94411) のコンドルールの形成条件を調査する.
- *これらの条件を既存のコンドルル形成モデルと比較する.
- * 初期の太陽星雲における塵/ガス比と熱現象を理解するために.
主な方法:
- *ハマダ・アル・ハムラ237号とクエ94411号の隕石から採取したコンドルルの分析.
- * コンドルル形成中の熱現象と化学条件の特徴.
- * 塵/ガス比率と凝縮配列の評価.
主要な成果:
- * コンドルルは,太陽の星雲の中の塵を蒸発させ,高エネルギーの熱現象を記録した.
- * 形成は,鉄・ニッケル金属の凝縮前に,温度≥1500Kの酸化条件下で発生した.
- *これらのコンドルールは,適度な揮発性元素の凝縮前に冷却ガスから分離された.
結論:
- * 形成環境は,塵の完全な蒸発を含む従来のモデルとは根本的に異なっていた.
- *これらの発見は,これまで考えられていたよりも極端な初期の太陽星雲を示唆しています.
- *この研究は,天体物理学的環境とコンドルル形成プロセスに関する新しい制約を提供します.
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