Alkam agejdan

23,000 seg telmas yemgaraden n yitran i d-yettbinen deg twenɣa-ayi. Asuneɣ yemmal-d d akken tilmas n yitran ṭṭafarent tameknut imalen deg telɣa yuzdawen seg teɣmert tazelmaṭ tafellayt (itran mellulen, izeqqlen s waṭas) ɣer teɣmert tayeffust taddayt (itran ur nzeqqel ara s waṭas), tagrawt-a tettwasemma swelkem agejdan.Akken i yella uẓuni niwezlanen imellalen,akken i yella sufell n welkem tagrawt nyizuncafcalen(subgiants), d tegrawt n yicafcalen (giants), dyifelcafcalen(supergiants) igebren seg - s unect n yisem-is - itran meqqren s waṭas s wassaɣ ɣertkura tanafukt.Ma dtafukttella deg tlemmast n welkem agejdan d itri yegdan 1 n tkura tanafukt, dwazal amagdezyegdan 4,8, d umatar n yini 0.66 (B-V color index) dteẓɣelt5.780 C d telmest nwaylalG2.

Alkam agejdanditesnalluntd azlem uddinan nyitranissiliɣ-d azal n 80% seg yitran yemgaraden deg umeɣrad, tessegraw-it-id yiwet n twenɣa,i wakken ad t-ittessesmel s unect n yini d tedwast nusfijjej.Itran n welkem agejdan ttwassnen s akkentafasan usfijjej-nsen d tin i d-yekkan seg tsedmirt nwezday aɣisan n uhidṛujindeg wul n yitri, dɣa anecta iga d snat n tsedmirin n wezday aɣisan i d-igellun s [[Hilyum|uhilyum].

Tawenɣa issegrawen ger n tkura n yitri d yini n yiniwaylal-isd tedwast n usfijjej-is tettwasemma susesmel n Hertzsprung–Russell,ma d tagrawt n yitran n ubaggus-a di twenɣa-ayi tettwasemma swelkem agejdan,acku tessiliɣ-d azal n 80% seg telmas n yitran yellan deg umeɣrad. Ma d isesmilen n yitran yeffɣen seg ubaggus-a agejdan ssesmilen-d 20% seg yitran n umeɣrad, dɣa ttemsegrawen-d di twenɣa ɣef sin n yibaggusen niḍen, yerna iglamen-nsen mgaraden s waṭas ɣef yiglamen n yitran n welkem agejdan, acku asufeɣ-nsen d ufares-nsen i tfasa yettuɣal ɣer tsedmirin niḍen anagarazday aɣisannuhidṛujini d-igellun s uhilyum.