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Updated: Jun 17, 2026

10:35
Bringing the Visible Universe into Focus with Robo-AO
Published on: February 12, 2013
銀河系の中央のブラックホールを周回する星の加速
1Department of Physics and Astronomy, UCLA, Los Angeles, California 90095-1562, USA. ghez@astro.ucla.edu
Nature
|October 3, 2000
まとめ
研究者は,我々の銀河の中心にある超大質量ブラックホールである Sagittarius A* (Sgr A*) の近くの星の加速を測定した. これは,その質量と位置に関するより正確なデータを提供し,銀河のダイナミクスに関する私たちの理解を向上させます.
科学分野:
- 天文学と天体物理学について
- 星の動力学 星の動力学
- 一般相対性理論とは
背景:
- 超大質量ブラックホール (SMBHs) は,銀河中心の重要な構成要素である.
- 前回の射手座A* (Sgr A*) の近くの星の速度測定は,SMBHの証拠を提供しましたが,大きな不確実性がありました.
- 恒星の加速度の正確な決定は,SMBHの性質を研究するためのより正確な方法を提供します.
研究 の 目的:
- 銀河の中心を周回する星の加速を正確に測定するために.
- 射手座A* (Sgr A*) の位置と質量の推定を精査する.
- 銀河中心のすぐ近くにある質量密度を調査するために.
主な方法:
- 観測天文学は,恒星の位置と速度を高精度で測定する.
- 引力力を推論するために,恒星の軌道動態の分析.
- ブラックホールの質量と位置を推定するためにケプラーの軌道力学の応用.
主要な成果:
- Sgr A*の近くにある3つの星の加速を測定し,太陽の周りの地球の加速に匹敵する.
- 銀河中心の推論された最小質量密度を数桁増加させた.
- ダークマスをSgr A*の0.05 +/- 0.04弧秒以内で位置づけました.
結論:
- 恒星の加速測定は,SMBHを特徴付けるためのより正確な方法を提供します.
- 結果は,Sgr A*の性質を強く制限し,SMBHとしての性質を確認した.
- 将来の恒星軌道観測は,おそらく15年以内に,完全な軌道周期の観測を可能にし,SMBHのパラメータをさらに洗練します.
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