Marxaladda ugu horreysa ee tooska ah ee masaafada xiddig (61 Cygni at 11.4 light-years) waxaa lagu sameeyay 1838 Friedrich Bessel oo adeegsanaya farsamada parallax. Cabbiraadaha parallax waxay muujiyeen kala goynta xiddigaha ee samooyinka. Ilaalinta xiddigaha labalaabka ah waxay heleen muhiimad sii kordheysa intii lagu jiray qarnigii 19aad. 1834, Friedrich Bessel wuxuu arkay isbeddellada dhaqdhaqaaqa saxda ah ee xiddigga Sirius wuxuuna soo saaray wehel qarsoon. Edward Pickering wuxuu helay laba-geesoodka ugu horreeya ee muuqaalka ah 1899 markii uu arkay kala qaybsanaanta joogtada ah ee khadadka muuqaalka ee xiddigga Mizar muddo 104 maalmood ah.
1834 kii