▁Sun . ▁E ta ▁S cul pt oris ▁is ▁class ified ▁as ▁a ▁sem ire g ular ▁variable ▁with ▁a ▁visual ▁magnitude ▁that ▁fl uct u ates ▁between ▁+ 4 . 8 0 ▁and ▁+ 4 . 9 0 , ▁The ▁p uls ations ▁have ▁periods ▁of ▁ 2 2 . 7 , ▁ 2 3 . 5 , ▁ 2 4 . 6 , ▁ 4 7 . 3 , ▁ 1 2 8 . 7 ▁and ▁ 1 5 8 . 7 ▁days . ▁On ▁average , ▁this ▁star ▁is ▁radi ating ▁over ▁a ▁thousand ▁times ▁the ▁lum inos ity ▁of ▁the ▁Sun ▁from ▁its ▁en larg ed ▁photos phere ▁at ▁an ▁effective ▁temperature ▁of ▁ 3 , 6 4 1   K . ▁ ▁References ▁ ▁Category : M - type ▁gi ants ▁Category : As ym pt otic - gi ant - branch ▁stars ▁Category : Sem ire g ular ▁variable ▁stars ▁ ▁Category : S cul pt or ▁( const ell ation ) ▁S cul pt oris , ▁E ta ▁CD - 3 3 ▁ 1 5 2 ▁ 0 0 2 4 2 9 ▁ 0 0 2 2 1 0 ▁ 0 1 0 5 <0x0A> </s> ▁William ▁Ren wick ▁R idd ell ▁( 6 ▁April ▁ 1 8 5 2 ▁– ▁ 1 8 ▁February ▁ 1 9 4 5 ) ▁was ▁a ▁Canadian ▁lawyer , ▁judge , ▁and ▁historian . ▁R idd ell ▁was ▁born ▁in ▁Hamilton ▁Township , ▁Ontario ▁and ▁attended ▁Cob ourg