Tropika jaro (konata anka? kiel suna jaro), por ?eneralaj celoj, estas la longo de la tempo kiun la Suno uzas por reveni al la sama posicio en la ciklo de sezonoj , kiel ?i estas vidite el la Tero . Tempoperiodo inter du sinsekvaj sunaj trapasoj tra la punkto de printempa ekvinokso nomi?as tropika jaro. La tropika jaro da?ras 365.24220 terajn diurnojn , t.e. ?i estas pli kurta je 20 minutoj kompare kun la stela jaro. Kiam oni parolas pri la jaro en ?iutaga vivo oni kutime parolas pri tropika jaro.

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