, ▁ 1 6 . 8 , ▁and ▁ 2 3 . 7 ▁days . ▁This ▁star ▁has ▁about ▁ 1 . 6 ▁times ▁the ▁mass ▁of ▁the ▁sun , ▁but ▁it ▁has ▁expanded ▁to ▁ 5 4 ▁times ▁the ▁Sun ' s ▁radius ▁and ▁sh ines ▁ 6 3 1 ▁times ▁as ▁bright ly ▁as ▁the ▁Sun . ▁The ▁effective ▁temperature ▁of ▁its ▁outer ▁atmosphere ▁is ▁ 4 , 0 0 9   K . ▁ ▁References ▁ ▁Category : M - type ▁gi ants ▁Category : As ym pt otic - gi ant - branch ▁stars ▁Category : Sem ire g ular ▁variable ▁stars ▁Category : V ir go ▁( const ell ation ) ▁Virgin is , ▁Nu ▁Category : D urch m uster ung ▁objects ▁Virgin is , ▁ 0 0 3 ▁ 1 0 2 2 1 2 ▁ 0 5 7 3 8 0 ▁ 4 5 1 7 <0x0A> </s> ▁The ▁ 2 0 1 9 – 2 0 ▁MR F ▁Challenge ▁Formula ▁ 2 0 0 0 ▁Championship ▁is ▁the ▁sevent h ▁running ▁of ▁the ▁MR F ▁Challenge ▁Formula ▁ 2 0 0 0 ▁Championship . ▁It ▁began ▁on ▁ 2 2 ▁November ▁ 2 0 1 9 ▁at ▁the ▁Dub ai ▁Aut od rome , ▁United ▁Arab ▁Em ir ates , ▁and ▁finished ▁on ▁February ▁ 1 6 ▁ 2 0 2 0 ▁at ▁the ▁Mad ras ▁Motor ▁Race ▁Track ▁in ▁Chen na i , ▁India . ▁The ▁series ▁was ▁held ▁over ▁ 1 5