[ η Crucis is located 64 light-years from the Sun. The system made its closest approach about 1.6 million years ago when it achieved perihelion at a distance of roughly 26 light years.[23]]This is an F-type main sequence star with a stellar classification of F2 V.[4] It has 130%[12] of the Sun's radius and shines with 7[13] times the luminosity of the Sun from an outer atmosphere with an effective temperature of 6,964 K.[11] Observations of the system using the Spitzer Space Telescope show a statistically significant infrared excess of emission at a wavelength of 70μm. This suggests the presence of a circumstellar disk. The temperature of this material is below 70 K.[18]
Eta Crucis has a pair of visual companions. Component B is a magnitude 11.80 star located at an angular separation of 48.30″ along a position angle of 300°, as of 2010. Component C has a magnitude of 12.16 and lies at an angular separation of 35.50″ along a position angle of 194°, as of 2000.[29]
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