Glossary term: 逃逸速度
Description: 逃逸速度是物體要永久逃離天體引力場所需的最小速度，在物理上它是一個標量，因此更準確的說法是“逃逸速率”，但“逃逸速度”這一術語更為常用。最簡單的情況是具有球對稱的天體，這對描述恆星和行星來說是一個很好的近似。在這種情況下，質量為m的天體，其中心距離為r的位置的逃逸速度可由公式√(2Gm/r)給出，其中G為引力常數。對於球形天體而言，其表面至中心的距離即為半徑，因此逃逸速度取決於天體的半徑和質量。例如，太陽表面的逃逸速度為617.5公里/秒（km/s），地球為11.2 km/s，而月球為2.4 km/s，這意味著在月球上物體擺脫其引力需要達到的速度比在地球上更低。
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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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