火か星せい年ねんじ字FuriganaMeanings1nounMartian yearAstronomical term for the orbital period of Mars around the Sun, approximately 687 Earth days.火か星せい年ねんは地ち球きゅうの約やく1.88年ねんに相そう当とうする。A Martian year is equivalent to about 1.88 Earth years.
