南極で測定された宇宙球体の収縮速度
S Taylor1, J H Lever, R P Harvey
1US Army Cold Regions Research and Engineering Laboratory, Hanover, New Hampshire 03755, USA.
Nature
|May 15, 1998
まとめ
研究者は,南極の氷から地外微小隕石を集め,その流入を正確に測定しました. 発見は,大気圏への入り口で,入射するサブミリメートルの宇宙塵の質量の約90%が失われたことを明らかにしています.
科学分野:
- 宇宙塵の研究 宇宙塵の研究
- 惑星科学は惑星科学である.
- 地質物理学 地質物理学とは地質物理学です.
背景:
- 微小隕石,地球外粒子<1mmは,地球によって蓄積された大部分の質量を表しています.
- 彼らは小惑星,彗星,惑星,およびプレソーラー粒子の洞察を提供します.
- 以前の流量測定は,気象による不確実性,収集の非効率性,年代測定の不適切性により不確実性がありました.
研究 の 目的:
- 以前の微小隕石流量測定の限界を克服するために.
- 宇宙球粒子の流動と質量分布を正確に決定する.
- マイクロメテオロイドの大気圏入り生存率のモデルを制限するために.
主な方法:
- 南極の水井からの数千の保存状態が良く,日付を付けられた微小隕石のコレクション.
- 50~700ミクロムの宇宙球体 (溶けた微小隕石) の分析.
- 融解していない微小隕石の豊富さを推定し,到着した総質量を計算する.
主要な成果:
- 宇宙球粒子の流量と質量分布の正確な推定.
- これは,大気圏に入るとき,入ってくる亜ミリメートル粒子の質量の約90%が蒸発することを示す.
- 深海の堆積物からガラスに富んだ小石球体や小石球体の損失を特定する.
結論:
- 南極の水井は,微小隕石の研究のためのユニークで信頼できる情報源を提供します.
- 大気圏への入り口は,到着した微小隕石の質量を大幅に減少させます.
- データは,微小隕石の生存確率を理解するための重要な制約を提供します.
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