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Updated: Jul 10, 2026

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Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
小惑星エリスの質量です
Michael E Brown1, Emily L Schaller
1Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, USA.
まとめ
研究者は,小惑星エリスの衛星であるディズノミアの軌道を正確に測定しました. これにより,彼らはエリスを決定することができました.
科学分野:
- 天文学と惑星科学 天文学と惑星科学
- トランス・ネプチューンのオブジェクト
- 矮惑星の特徴について
背景:
- 矮惑星エリスには衛星ディズノミアがあるが,その軌道パラメータと惑星系の総質量は以前は不明だった.
- これらのパラメータを理解することは,エリスとその形成の歴史を特徴づける上で極めて重要です.
研究 の 目的:
- ディスノミアがエリスの周りを回る軌道パラメータを正確に決定する.
- エリス-ディズノミア系の質量を計算する.
- ディスノミアの形成メカニズムを推論する.
主な方法:
- ケック天文台とハッブル宇宙望遠鏡からの新しい観測データを活用した.
- ディスノミアの軌道半径と周期を決定するために,観測を分析した.
- システムの質量を計算するために軌道力学を応用した.
主要な成果:
- ディスノミアは,半径37,350 +/- 140 kmの円形軌道でエリスの周りを回っています.
- ディスノミアのエリスの周回周期は15.774 +/- 0.002日です.
- 計算されたエリスの質量は1.67 x 10^22 +/- 0.02 x 10^22 kgで,これは冥王星の質量の約1.27倍です.
結論:
- 決定された軌道パラメータは,巨大衝突後の残骸から形成されたディズノミアと一致しています.
- 現在,エリスの質量は正確に制限されており,太陽系外部の比較惑星学に役立ちます.
- この研究は,矮惑星系とその動的進化に関する私たちの理解を洗練します.
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