The two stars are separated by 0.46° in the sky. Because they are close to the ecliptic, they can be occulted by the Moon and, very rarely, by planets. The next occultation of ρ¹ Sagittarii by a planet will take place on 23 February 2046, when it will be occulted by Venus.
In Chinese, 建 (Jiàn), meaning Establishment, refers to an asterism consisting of ρ¹ Sagittarii ξ² Sagittarii, ο Sagittarii, π Sagittarii, 43 Sagittarii and υ Sagittarii. Consequently, ρ¹ Sagittarii itself is known as 建五 (Jiàn wǔ, English: the Fifth Star of Establishment.)
- "HD 181577 -- Variable Star". SIMBAD Astronomical Database. Retrieved 2007-03-29.
- "HD 181645 -- Star". SIMBAD Astronomical Database. Retrieved 2007-03-29.
- (Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 5 月 11 日
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