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astronomical unit 天文單位〔地球至太陽間的平均距離〕。

astronomical year

From 12 to 14 may , this mysterious string of comet will pass earth at a mere 0 . 0735 astronomical unit i . e . 29 lunar distances . astronomers expect that the biggest fragment will shine as bright as magnitude 5 5月12至14日,這串神秘的彗星會于地球0 . 0735天文單位即地月距離的29倍外掠過,天文學家預測它最大的碎片會亮至5等。

It dwells in the kuiper belt at about 42 au away and moves around the sun every 288 years 1 astronomical unit the distance between the earth and the sun , about 150 million kilometers 據初步計算,這顆天體距離地球約4 2個天文單位個天文單位太陽和地球的距離,即約15億公里,運行一周需時288年。

Astronomers believe that comets originate from the oort cloud which is located 5 , 000 to 100 , 000 astronomical units from the sun 天文學家相信彗星誕生于距離太陽五千至十萬個天文單位的奧爾特云。

Pluto , the remotest planet in the solar system currently known , is about 80 astronomical units away from the sun 太陽系與行星太陽系目前最遙遠的行星冥王星距離太陽約

Recall that one astronomical unit is the average distance between the sun and the earth 來表示,一天文單位即太陽和地球的平均距離請參閱

The convenient length unit for measuring distances between planets is the astronomical unit 在天文學上,太陽系內天體的距離慣用