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Bringing the Visible Universe into Focus with Robo-AO
Published on: February 12, 2013
冥王星の2つの新しい衛星の発見
H A Weaver1, S A Stern, M J Mutchler
1The Johns Hopkins University Applied Physics Laboratory, Space Department, 11100 Johns Hopkins Road, Laurel, Maryland 20723-6099, USA. hal.weaver@jhuapl.edu
Nature
|February 24, 2006
まとめ
天文学者は,冥王星を周回する2つの新しい衛星を発見し,それを複数の衛星を持っていることが知られている最初のカイパーベルトオブジェクトにしました. これらの小さな月,P1とP2は,冥王星と同じ平面を軌道に乗っています.
科学分野:
- 天文学 (astronomy) 天文学 (astronomy) とは,天文学 (astronomy) とは,天文学 (astronomy) とは,天文学 (astronomy) とは
- 惑星科学は惑星科学である.
- 太陽系探査 太陽系探査について
背景:
- 冥王星の唯一知られている衛星,ハロンは1978年に発見され,直径は冥王星の約半分です.
- 前回の冥王星周辺の衛星探査は,敏感度が限られ,約150km未満の小物体を検出できませんでした.
- クイパーベルトオブジェクトの冥王星は,この発見の前に複数の衛星を持っていることは知られていなかった.
研究 の 目的:
- 冥王星を周回する追加の衛星の存在を検索し,確認する.
- 新しく発見された衛星のサイズ,暫定軌道,軌道特性を特徴付けるため.
主な方法:
- 冥王星周辺の小さな天体を検出するために,高度な観測技術を活用しました.
- 新しい衛星 (S/2005 P1とS/2005 P2) を特定し,暫定的に指定するために,観測データを分析した.
主要な成果:
- 冥王星の周りを回っている2つの新しい衛星,暫定指定S/2005 P1 (P1) とS/2005 P2 (P2) が発見されました.
- P1は直径が60km~165kmと推定され,P2はP1より約20%小さい.
- P1とP2は,チャロンと同じ軌道平面の円周軌道に従っているように見えますが,推定軌道周期はそれぞれ約38日と25日です.
結論:
- 冥王星は,複数の衛星をホストしていることが確認された最初のカイパーベルトオブジェクトです.
- この発見は,太陽系外部の衛星系形成と動態に関する我々の理解を広げている.
- 確固たる軌道を導き,新しい衛星の物理的特徴を洗練するために,さらなる観測が必要である.
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