Tahun tropis

Tahun tropis (juga tahun matahari) merupakan tahun yang didasarkan pada revolusi bumi terhadap titik musim semi, yaitu terhadap awal berbagai musim. Tahun ini lamanya rata-rata 365.2421 siang hari atau 365 hari 5 jam 48 menit 46 detik.

 Referensi 

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