Glossary term: 可觀測宇宙
Description: 可觀測宇宙指的是我們能看到的宇宙區域，它是一個以我們為中心的球體。可觀測宇宙的半徑取決於自宇宙誕生以來，光能向我們傳播的距離。位於可觀測宇宙邊界的區域距離我們非常遙遠，以至於在過去的 140 億年裡，它們的光線才剛剛有足夠的時間到達我們這裡；換句話說，就也是宇宙的年齡。
我們現在所能看到的最遙遠的宇宙區域距離我們超過 400 億光年。這是因為從這些區域發出的光到達我們這里之後，宇宙已經膨脹了很多。來自可觀測宇宙之外的天體的光還沒有足夠的時間到達我們這裡。
我們等待的時間越長，光線向我們傳播的時間就越長，可觀測宇宙也就越大。宇宙中的其他觀測者也有自己的可觀測宇宙：一個以他們為中心的球體，其半徑是其他區域的光線能夠到達他們的最遠距離。
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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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