Glossary term: 絕對星等
Description: 絕對星等是一種測量方法，有兩種不同的定義。兩者都與天體在一組特殊條件下的亮度有關。定義了絕對星等，我們就可以比較處於不同距離的天體的固有屬性。絕對星等與視星等不同，視星等測量的是從觀測者所在位置看到的天體的亮度。
對於太陽系外的天體，如恆星和星系，絕對星等的定義是：從 10 秒差距的標準距離處觀察天體所得的視星等，且忽略星際消光的影響。通過這個標準化的數字，我們可以比較不同天體的固有亮度。
對於太陽系內的天體，如小行星，絕對星等的定義是：當天體與太陽和觀測者都相距一個天文單位，且相位角為0°時，所得的視星等。請注意，若觀測者位於地球，則太陽系內的天體永遠不可能符合這些條件。但該定義去除了取決於天體和觀測者位置的因素，以便我們比較不同位置的太陽系天體的固有屬性。
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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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