Glossary term: 度
Description: 在數學中，度（符號為°）是角度的單位。一度是整個圓周的1/360。它既可以用十進制小數來表示，也可以被細分為角分（符號為′）和角秒（符號為″）。一度被分為60角分，一角分被分為60角秒。一角秒是一度的1/3600，是一個極小的角度。
度數可用於表示天體的視尺寸（見角直徑）及其在天球上的位置（另見：赤緯、赤經、高度角和方位角，對應於地球上：緯度和經度）。它們也用於測量天球上的天體之間的角距離。向前伸直肐膊時拳頭的寬度約為10°，從地平到天頂的距離是90°。根據尺度的不同，望遠鏡的分辨率和視場可以用度、角分或角秒來表示。
度數的另一含義是溫度的單位，使用時需標明華氏溫標或攝氏溫標。攝氏溫標定義海平面上水的冰點為0°C，水的沸點為100°C。 攝氏溫標下，一度對應的溫度變化與一開爾文是相同的，但它們的零點不同。開爾文溫標的零點是絕對零度，即最低溫度-273.15°C。在較早的華氏溫標中，一度對應的溫度變化與5/9攝氏度（或開爾文）相同。
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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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