銀河の超大群であるラニアケアは,
R Brent Tully1, Hélène Courtois2, Yehuda Hoffman3
1Institute for Astronomy, University of Hawaii, Honolulu, Hawaii 96822, USA.
Nature
|September 5, 2014
まとめ
天文学者は,宇宙構造を定義するために,銀河の特異的な速度をマッピングしました. 彼らは,異なる銀河の流れに基づいて,新しい超銀河団,ラニアケアを特定し,宇宙のウェブで私たちの家を明らかにしました.
科学分野:
- コスモロジー・コスモロジーとは
- 天体物理学 天体物理学
- 銀河の形成と進化について
背景:
- 銀河は,クラスター,フィラメント,空洞に編成され,大規模な宇宙のネットワークを形成しています.
- 既存の超大群の定義には,正確さや明確な境界線が欠けている.
- 重力による宇宙膨張からの偏差である特殊速度は,物質の分布をマッピングする新しい方法を提供します.
研究 の 目的:
- 特殊な速度を用いて宇宙構造の地図を作成する.
- 重力フローパターンを基にスーパークラスタを特定し,定義する.
- 我が家のスーパークラスタの境界線を定めるために.
主な方法:
- 測定された銀河の距離と速度から派生した特異的な速度のカタログを使用しました.
- 特殊な速度場を分析して,分岐点を見つけ,流域の分岐点に類する.
- 超群集は,異なった特異的な速度流の表面によって囲まれた体積として定義されます.
主要な成果:
- 特殊な速度に基づいた宇宙構造の新しい地図を生成しました.
- 私たちの地域を取り巻く異なった特異的な速度流の表面を特定しました.
- これらの異なる流れに基づいて,ラニアケアと呼ばれる私たちのホームスーパークラスターの範囲を定義しました.
結論:
- 特殊速度マッピングは,超群集のような大規模な構造を定義するための正確な方法を提供します.
- 特定されたラニアケア超群集は,局所宇宙の重要な容量を網羅しています.
- スーパークラスターのこの新しい定義は,宇宙のウェブ内の私たちの位置をより明確に理解することを提供します.
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