HD 39901 is an orange hued star located in the constellation Columba. It is also called HR 2069, which is the star's Bright Star Catalog designation. Eggen (1989) lists it as a member of the old disk population.^[11]

Despite the HR designation, the object has an apparent magnitude of 6.54,^[3] slightly past the limit for the naked eye visibility. As a result, it is barely visible to the unaided eye in the best conditions. Parallax measurements from the Gaia spacecraft place the object 639 light years away.^[2] It is approaching the Solar System with a heliocentric radial velocity of −10.3 km/s.^[6] At that distance, HD 39901's brightness is diminished by 0.33 magnitudes due to interstellar dust.^[15] It has an absolute magnitude of −0.03.^[1]

This is an evolved red giant star with a stellar classification of K3 III.^[4] It has a comparable mass to the Sun^[7] but has expanded to 21.9 times the latter's girth.^[8] It radiates 143 times the luminosity of the Sun^[9] from its photosphere at an effective temperature of 4,373 K.^[10] HD 39901 is slightly enriched in heavy elements with a metallicity 120% that of the Sun's.^[11] Like most giants, it spins slowly, having a projected rotational velocity lower than 1.6 km/s.^[12]

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