HD 194783 (HR 7817; 2 G. Microscopii) is a solitary star located in the southern constellation of Microscopium near the border with Sagittarius. It is barely visible to the naked eye as a bluish-white-hued point of light with an apparent magnitude of 6.08. The object is located relatively far at a distance of 740 light-years based on Gaia DR3 parallax measurements, but it is drifting closer with a heliocentric radial velocity of . At its current distance, HD 194783's brightness is diminished by an interstellar extinction of 0.31 magnitudes and it has an absolute magnitude of either −0.59 or −1.10, depending on the source.
HD 194783 has a stellar classification of B8 II/III, indicating that it is an evolved B-type star with the blended luminosity class of a bright giant and a lower luminosity giant star. It has also been given a class of B9pHgMn, indicating that it is a chemically peculiar mercury-manganese star. It has 4.03 times the mass of the Sun and a slightly enlarged radius 4.19 times that of the Sun's. It radiates 390 times the luminosity of the Sun from its photosphere at an effective temperature of . The heavy metal (iron) to hydrogen ratio–what astronomers dub as the star's metallicity–is 63% that of the Sun's. HD 194783 is estimated to be approximately 70 million years old.
In 1989, HD 194783 was reported to be a spectrum variable with a period of 6 days. The projected rotational velocity of the star is not known, but it is said to be no higher than . HD 194783 was also observed to have a relatively weak magnetic field of about −43 gauss.
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