HD 178322, also known as HR 7257 or rarely 45 G. Coronae Australis, is a double-lined spectroscopic binary located in the southern constellation Corona Australis. It has a combined apparent magnitude of 5.86, making it faintly visible to the naked eye under ideal conditions. The system is located relatively far at a distance of roughly 1,550 light-years based on Gaia DR3 parallax measurements, and it is currently receding with a heliocentric radial velocity of . At its current distance, HD 178322's brightness is diminished by an extinction of 0.28 magnitudes and it has an absolute magnitude of −2.31. The system has a high peculiar velocity of , indicating that it may be a runaway star system; it is said to be part of the Scorpius-Centaurus Association.
The components of HD 178322 are both B-type main-sequence stars with stellar classifications of B5 V and B6 V respectively. Both stars have roughly 4.4 times the mass of the Sun and they spin moderately with projected rotational velocities of . The primary has 3.26 times the radius of the Sun and it radiates 11,749 times the luminosity of the Sun from its photosphere at an effective temperature of . The companion has 3.07 times the Sun's girth and it radiates 513 times the luminosity of the Sun from its photosphere at an effective temperature of . Both stars take roughly 12 days to complete a relatively circular orbit at a separation of . The system is estimated to be 50 million years old.
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