火星 の 表面 の 重力 線 は,ゲール クレーター の 岩底 の 密度 が 低い こと を 示し て い ます
Kevin W Lewis1, Stephen Peters2, Kurt Gonter2
1Earth and Planetary Sciences Department, Johns Hopkins University, Baltimore, MD 21218, USA. klewis@jhu.edu.
まとめ
キュリオシティ・ローバー
科学分野:
- 惑星科学
- 地理学
- 火星探査
背景:
- 重力測定は重力場を正確に測定し,惑星の内部構造の研究に役立ちます.
- 火星の探査機"キュリオシティ"には アクセロメーターが搭載され 航行や姿勢を決定します
研究 の 目的:
- 重力加速度の変化を測定するために キュリオシティの加速度計を再調整します
- グラビメトリーを使って ゲールクレーターの地下岩の密度を推測する
主な方法:
- 重力場の変動を検出するためにローバーの加速度計の再調整.
- ローバーの上昇時の高さによる重力場の減少を測定する.
主要な成果:
- ゲールクレーターの堆積岩の密度は1680 ± 180 kg/m3である.
- この密度は予想より低く,高孔性を示唆しています.
結論:
- 推論された低い岩の密度は,ゲールクレーターの堆積岩の有意な多孔性を示しています.
- この発見は 火星岩の埋葬の深さを 制限しています
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