火星 に 液体 の 水 が ある と いう ラダー の 証拠
R Orosei1, S E Lauro2, E Pettinelli2
1Istituto di Radioastronomia, Istituto Nazionale di Astrofisica, Via Piero Gobetti 101, 40129 Bologna, Italy. roberto.orosei@inaf.it.
Science (New York, N.Y.)
|July 27, 2018
まとめ
科学者たちはレーダーデータを用いて 火星の南極層の沈殿地の下に 液体の水の証拠を発見した. この発見は 赤い惑星に 安定した地下水が存在する可能性を示唆しています
科学分野:
- 惑星科学
- 地理学
- 天体生物学
背景:
- 火星の液体の水の存在は 惑星科学の重要な問題です
- 以前の研究では 地下水が存在する可能性が示唆されていました 特に極地では 直接的な証拠は ありませんでした
研究 の 目的:
- 液体の水の証拠を火星の南極の 層状の貯蔵物を調査する
- レーダーデータを分析して 水分を含有する物質の異常を特定する
主な方法:
- マース・エクスプレス号に搭載された火星高度レーダー (MARSIS) を利用した.
- 2012年5月から2015年12月にかけて プランウム・オースタレ地域を調査した.
- 地下レーダーの反射を分析した
主要な成果:
- 南極層の地下レーダーで 異常な反射が観測された
- 定量分析では,この特性の相対的介電性 (> 15) が高いことが示された.
- 明るい反射と高い伝導性は,水分を保持する材料と一致しています.
結論:
- 観測されたレーダーシグネチャは 火星の氷の層の下に 安定した液体の水が存在する事を強く示唆しています
- この発見は火星の極地層の底部に 液体の水が存在する 最初の直接的な証拠です
- この発見は火星の潜在的居住可能性に 重要な意味を持ちます
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