This is a so-called mild barium star, as identified by the presence of a weak absorption line of singly-ionized barium atoms at a wavelength of 455.4 nm. Such stars display an atmospheric overabundance of carbon and the heavy elements produced by the s-process, which was most likely transferred into the atmosphere by a wide binary stellar companion. However, in the case of 24 Aquilae, the abundances of heavy elements are near normal.[4]
At an estimated age of a half billion years,[4] 24 Aquilae is a evolvedgiant star with a stellar classification of K0 IIIa.[4] It has more than double the mass of the Sun, 11 times the Sun's radius, and shines with 56 times the Sun's luminosity.[1] It is radiating this energy into space from its outer atmosphere at an effective temperature of 4,733 K.[1] This heat is what gives it the cool orange hue characteristic of a K-type star.[7]
^Keenan, Philip C.; McNeil, Raymond C. (1989), "The Perkins catalog of revised MK types for the cooler stars", Astrophysical Journal Supplement Series, 71: 245, Bibcode:1989ApJS...71..245K, doi:10.1086/191373.
