三角銀河 (M33) の幾何学的な距離と自己運動
Andreas Brunthaler1, Mark J Reid, Heino Falcke
1Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, 53121 Bonn, Germany. brunthaler@jive.nl
Science (New York, N.Y.)
|March 5, 2005
まとめ
天文学者はVery Long Baseline Arrayを使用して,三角銀河 (M33) の距離と運動を測定しました. これは,局所グループの動力学と銀河の質量推定に関する新しい洞察を提供します.
科学分野:
- 天文学と天体物理学について
- コスモロジー・コスモロジーとは
- 銀河のダイナミクス
背景:
- 三角銀河 (M33) は,ローカルグループの重要な構成要素である.
- 正確な距離と運動の測定は,銀河の相互作用と質量を理解するために不可欠です.
研究 の 目的:
- マザー観測を用いて三角銀河 (M33) までの距離を正確に測定する.
- 銀河系に対するM33の自己運動を決定する.
- 局所群のダイナミックモデルを精錬し,銀河の質量を推定する.
主な方法:
- 非常に長いベースライン配列 (VLBA) を使用して,M33.3のH2Oマザーを観測しました.
- マザーソースの角回転と自律運動を測定した.
- 回転速度と傾きと速度を比較して計算した距離.
主要な成果:
- M33までの距離は730 ± 168キロパーセックスの距離を決定した.
- 190 ± 59 km/sで,銀河系に対するM33の速度を測定した.
- 結果は,最近のセフェイドの距離測定と一致しています.
結論:
- 採用されたマザー観測技術は,銀河外距離の決定のための信頼できる方法を提供します.
- これらの測定は,ローカルグループのためのダイナミックなモデルを開発するのに役立ちます.
- M31,M33,そして天の川銀河の質量とダークマターのハロのよりよい推定を可能にします.
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