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Updated: Jul 8, 2026
11:34
Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
火星探査ローバー"スピリット"と"オポチュニティ"による大気画像撮影結果
M T Lemmon1, M J Wolff, M D Smith
1Texas A&M University, College Station, TX 77843, USA. lemmon@tamu.edu
Science (New York, N.Y.)
|December 4, 2004
まとめ
火星探査機"スピリット"と"オポチュニティ"は,大気中の塵を測定し,光学的な深さが時間の経過とともに減少していることを発見しました. 塵の分布は均一で,スケールの高さは約11.6kmでした.
科学分野:
- 惑星科学 惑星科学
- 大気科学 大気科学
- 火星探査 火星探査
背景:
- 火星の大気条件を理解することは,ミッション計画と地表観測の解釈に不可欠です.
- 以前の研究では,火星の大気中の塵をモニタリングしましたが,詳細な垂直分布と粒子の大きさのデータは貴重なものです.
研究 の 目的:
- ローバーのデータを用いて,グセフクレーターとメリディアニ・プラニュムの大気光学深さと塵の性質を測定および分析する.
- 火星の空気中の塵の垂直分布と粒子の大きさを決定する.
主な方法:
- スピリット・ローバーとオポチュニティ・ローバーのデータを活用して,可視大気圏の光学深さを測定した.
- 最初の90ソルミッションにおける光学深さの傾向を分析した.
- 大気測定から計算された塵スケールの高さと平均粒子の半径.
主要な成果:
- GusevクレーターとMeridiani Planumの両方で0.9の可視大気光学深度が記録されました.
- 大気中の光学深度は,ミッション中に1ソルあたり0.60.7%減少した.
- グセフクレーターでの塵の垂直分布は,スケール高さ11.56 ± 0.62 kmで均等な混合を示した.
- 両箇所での平均塵粒子の半径は,約1.5マイクロメートルと決定された.
- 視界と赤外線の光学深度比を2.0 ± 0.2と計算した.
結論:
- 火星の大気は,主要なミッションの期間中に,塵の光学的な深さの測定可能な減少を示した.
- 粉塵の垂直分布は,グセフクレーターでよく混ざった大気を示唆しています.
- 決定された塵の性質は,気候モデルと将来の火星ミッションのための貴重なデータを提供します.
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