2024 ni umwaka muremure: vyaje gute, kubera iki ukwa kabiri kugira umusi w’inyongera?

Uno mwaka wa 2024 uzomara imisi 366 aho kumara 365 isanzwe imenyerewe, kubera ni umwaka muremure (année bissextile).

Buri myaka ine twama tubona iki kintu kidasanzwe ku birangamisi vyacu, ariko none ni kubera iki haba ino myaka miremire, vyatanguye ryari?

Mu kwishura ibi bibazo, ni ugusubira inyuma ku butegetsi bwa kera cane bw’Abaromani (Rome antique), haraciye imyaka irenga 2000, igihe abahinga bahinyura ko ikirangamisi c’ico gihe kitari kijanye n’umwaka w’izuba (année solaire).

Umwami w’abami (empereur) Juliusi Sezari (Jules César) ni we yagize iciyumviro co gusaba umuhinga mu vy’ikirere Sosigène d'Alexandrie ko yomufasha agashinga ikirangamisi cosubirira ic’Abaromani (calendrier romain), cashobora kujana n’ibihe be n’ukungene isi izunguruka.

Isi yacu ntikoresha imisi 365 yonyene mu kurangiza urugendo ruzunguruka izuba, nk’uko bamwe bavyibaza, ariko hiyongerako amasaha 5, iminota 48 n'amasegonda 56.

Ni co gituma Sosigène yabahaye ikirangamisi cari cegereye ic’Abanyamisiri, cari gifise imisi 365 yiyongerako umusi umwe uko imyaka ine iheze kugira ngo kijane n’umwaka w’izuba.

Uko ni ko havutse ikirangamisi citiriwe Jules (calendrier julien), izina ry’uwatanze iki ciyumviro.

Umusi wiyongera ku wa 24 Ruhuhuma (2)?

Hagati aho, iki kirangamisi cagenda kigira ibibazo ku buryo vyabaye ngombwa ko kigenda gisubirirwa bukebuke n’ikirangamisi citiriwe Papa Grégoire XIII (calendrier grégorien) kuva mu 1582, ari na co dukoresha ubu.

Nk’uko ikirangamisi citiriwe Jules (calendrier julien) gisaba umusi w’inyongera uko imyaka ine iheze, Abaromani bafashe ingingo ko uwo musi wokwongerwa ku kwezi kwa Ruhuhuma (2), ico gihe kwari ukwezi kwa nyuma kw’umwaka.

Izina ngo umusi w’inyongera (jour bissextile mu gifaransa) riva mu rurimi rw’ikilatini "ante diem bis sextum Kalendas Martias" (umusi wa gatandatu imbere y’ikirangamisi ca Ntwarante), ni ukuvuga ku wa 24 Ruhuhuma. Kubera rero yari amajambo menshi barondeye kuyavuga mu mpfunyapfunyo, aho bafashe "bis sextus": bissextile mu gifaransa.

Haciye imyaka, Papa Grégoire XIII yafashe ingingo yo "guhinyanyura" ikirangamisi.

Imwe mu mpinduka yabaye iyo gushinga umusi w’inyongera w’imyaka miremire ku wa 29 Ruhuhuma awukura ku wa 24 nk’uko vyari bimeze ku kirangamisi ca Jules.

Inyishu ishingiye ku biharuro

Ku nama yagiriwe n’umuhinga mu vy’ikirere w’umu-Jésuite Christophe Clavius, Papa yategetse kandi ko umusi wakurikira uwa kane itariki 4 Gitugutu 1582 wategerezwa kuba uw’igenekerezo rya 15 Gitugutu mu gufuta imisi cumi, ivyatumye akuraho igihengeri cari kihari ufatiye ku kirangamisi c’izuba.

Mu ntumbero yo gukuraho burundu iki gihengeri, haciye haba uburyo budasanzwe bwo guharura imyaka miremire (années bissextiles).

Mu bisanzwe, imyaka iba miremire iyo ishobora kugaburwa na kane, ariko ntiba miremire iyo ishobora kugaburwa na 100 ikaba idashobora kugaburwa na 400. Kuri iyi mvo, imyaka 1800 na 1900 mtiyabaye imyaka miremire, ariko umwaka wa 2000 warabaye umwaka muremure.

Kuri iyo mvo nyene, imyaka ya 2100, 2200 na 2300 ntizoba imyaka miremire.

Ikirangamisi kidashingiye kw’idini?

Uru rukurikirane rw’impinduka rwavuyemwo ikirangamisi ca none, ari co tuzi nk’ikirangamisi ca Grégoire (calendrier grégorien).

Kuva habaye iyo mpinduka ya nyuma, ikirangamisi ntikirigera gisubira guhindurwa.

Hagati aho, mu bihugu bimwe bimwe nk’Ubufaransa, harabaye ingendo zo gushaka kugihindura. Mu 1792, mu gihe c’Amahindurantwaro y’Ubufaransa (Révolution française), Ubufaransa bwashinze ikirangamisi ca repubulika (calendrier républicain), cashinzwe n’umuhinga mu biharuro Gilbert Romme.

Iki kirangamisi carondera gukuraho amazina ashingiye kw’idini maze amezi ahabwa amazina mashasha - bafatiye ku bintu vyo mu buzima busanzwe no ku burimyi – kinahindura n’imisi amezi yategerezwa kumara.

Ariko iki camaze umwanya urume rumara: ubutegetsi bwa Napoléon Bonaparte bumaze gusenyurwa mu mwaka wa 1814, Ubufaransa bwaciye bwihutira gusubira ku kirangamisi cashinzwe na Papa Grégoire XIII cari ciyumviriwe na Jules César.