parsecn. 秒差距(天體距離單位)學術名詞秒差距:計量學、測量學、高中物理學、物理學、航空太空、氣象學秒差矩{天文}:物理學英文釋義a unit of astronomical length based on the distance from Earth at which stellar parallax is 1 second of arc; equivalent to 3.262 light years