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Surface Properties of Synthesized Nanoporous Carbon and Silica Matrices
Published on: March 27, 2019
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予期せぬ小惑星 (101955) ベヌの表面
D S Lauretta1, D N DellaGiustina2, C A Bennett2
1Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ, USA. lauretta@orex.lpl.arizona.edu.
Nature
|March 21, 2019
まとめ
NASAのOSIRIS-RExミッションは 惑星ベヌの表面が 予想とは違っていることを発見しました この予期せぬ地形は 原始的で 揮発性物質に富んだ小惑星の 原始的なサンプルを回収する上で 課題を提示しています
科学分野:
- 惑星科学
- 天文地質学
- 天体化学
背景:
- ベヌ小惑星は 原始的なB型小惑星で 地球上の生物学的分子と水の潜在的源です
- ベヌの有機に富んだ水分組成は 炭酸性コンドライトと関連していますが 隕石は変化しています
- OSIRIS-RExのミッションは,地上汚染の影響を受けていない,原始的なベヌのサンプルを返還することを目的としています.
研究 の 目的:
- ベヌの初期のOSIRIS-REx観測と遭遇前の予想を比較する.
- ベヌから原始のサンプルを 送還する可能性を 評価するためです
- ベヌの表面の性質とサンプル収集への影響を理解するために
主な方法:
- OSIRIS-REx宇宙船の機器を活用して地球を特徴づけました
- サブセンチメートルスケールで表面の特性を記録する高解像度イメージングを行いました.
- ベヌの表面の観測モデルと比較して 初期の観測データを分析した.
主要な成果:
- ベンヌの大体成分は 水分と揮発性物質が豊富で 予想通りです
- 表面イメージングは,予期せぬ多様性を明らかにしました アルベド,質感,粒子のサイズ,および荒さ,ミッション設計の仕様を超えています.
- 衝突前のモデルは,観測された異質性とは対照的に,センチメートルスケールの粒子を持つ滑らかな表面を予測しました.
結論:
- ベンヌの多様で荒れた表面は,計画されたサンプリング戦略に重大な課題をもたらします.
- 十分な大きさ (5~20m) の危険のないサンプル採取場所を特定することは,予想以上に困難です.
- ベヌの表面の予期せぬ性質によって 試料の採取の成功は困難です
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