The pair was first discovered by astronomer W.H. van den Bos in 1944.[12] The primary has an apparent magnitude of 7.30 while the secondary has an apparent magnitude of 7.50.[3] Their current separation is 0.114",[8] making it difficult to resolve their individual properties; the companion is located at a position angle of 267° as of 1964.[3] The period of Tau2 Gruis is not well known,[13] but it is estimated to be 7.423 years.[8] Subsequent observations suggest that the pair may be spurious.[13] This system is often confused with HD 216655, a slightly brighter binary system.[14] HD 216655 is located 93.9" away from Tau2 Gruis and they appear to share a common proper motion.[3]
^ abHouk, Nancy (1978). Michigan catalogue of two-dimensional spectral types for the HD stars: Declinations −53° to −40°. Vol. 2. Bibcode:1978mcts.book.....H.
^Cousins, A. W. J.; Stoy, R. H. (1962). "Photoelectric magnitudes and colours of Southern stars". Royal Greenwich Observatory Bulletins. 64: 103. Bibcode:1962RGOB...64..103C. S2CID118805499.
^Gould, Benjamin Apthorp (1878). "Uranometria Argentina : brillantez y posicion de las estrellas fijas, hasta la septima magnitud, comprendidas dentro de cien grados del polo austral : con atlas". Resultados del Observatorio Nacional Argentino. 1. Bibcode:1879RNAO....1.....G.
^van den Bos, W. H. (September 1947). "Measures of Double Stars-25th Series". Circular of the Union Observatory Johannesburg. 105: 134–171. Bibcode:1947CiUO..105..134V.
^Wagman, Morton (2003). Lost Stars: Lost, Missing and Troublesome Stars from the Catalogues of Johannes Bayer, Nicholas Louis de Lacaille, John Flamsteed, and Sundry Others. Blacksburg, VA: The McDonald & Woodward Publishing Company. p. 162. ISBN978-0-939923-78-6.