Description: 有質量的物體會使經過其引力影響範圍附近的光線發生彎曲。愛因斯坦的廣義相對論預言了這種效應，並在 1919 年日食期間首次被觀測到，測量發現太陽附近幾顆恆星發出的星光發生了彎曲。引力透鏡作用在質量非常大的物體上最為明顯，如星系或星系團。如果地球上的觀測者正在觀測一個光線被（"透鏡"）彎曲的遙遠天體，這個天體的成像會出現扭曲。這種扭曲總是意味著光線的（縮小）放大，通常能讓我們更好地看到暗淡的背景天體。當透鏡有足夠的質量集中在一個小角度區域時，同一背景物體就會產生多個圖像，每個圖像的光線到達觀察者的時間都不同。測量這些所謂的 "時間延遲 "是確定銀河系外哈勃常數值的最佳方法之一。另一方面，來自透鏡的多幅圖像可以讓我們利用建模分析精確地確定其質量。這是一種非常有用的方法，可以用來尋找星系的質量，特別是星系團的質量。

Related Terms:

• 暗物質
• 銀河系
• 星系團
• 超大質量黑洞
• 哈勃參數

Term and definition status: The original definition of this term in English have been approved by a research astronomer and a teacher
The translation of this term and its definition is still awaiting approval

This is an automated transliteration of the simplified Chinese translation of this term

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