{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.667","julian_year":2026.667,"time":"2026-09-01T18:53:56.150Z","years_from_j2000":26.667,"frame":"date","applied":"Proper motion, then precession and nutation. The catalogued J2000 position is carried along the great circle the object's own published motion puts it on, at a constant velocity, and the result is referred to the true equator and equinox of this instant. Those are separate things: the motion moves the object, and the rotation turns the grid under it by about fifty arcseconds a year, with nutation adding up to another seventeen.","excluded":"Parallax, the radial-velocity perspective term, aberration and refraction; each is below the accuracy of the catalogued positions themselves. An object with no published proper motion comes back where the catalogue has it rather than at a fabricated zero, and says so with a null pm_ra_mas_yr. A body with no fixed position is not propagated at all — its place comes from an ephemeris, which is what /api/v1/visible answers with."},"slug":"hd-28639","name":"HD 28639","class":"k2_3iii_iv_orange_giant","category":"star","object_type":"K2/3III/IV orange giant","mag":7.73,"mag_band":"V","abs_mag":0.967,"abs_mag_band":"V","distance_ly":734.5863540252908,"distance_method":"parallax","ra_deg":67.43097,"dec_deg":-29.029777,"epoch_ra_deg":67.698595,"epoch_dec_deg":-28.970828,"epoch_moved_arcsec":1.199,"pm_ra_mas_yr":-32.44,"pm_dec_mas_yr":-31.12,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Eridanus","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-28639","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"04297-2902","companions":[{"measured":2015,"magnitude":10.9,"components":null,"discoverer_code":"HDS 579","separation_arcsec":22.6,"position_angle_deg":58}],"spectral_type":"K2/3III/IV","color_index_bv":1.278,"luminosity_solar":35.74374062644807,"radial_velocity_km_s":0,"spectral_type_source":"SIMBAD (1982MSS...C03....0H, quality E)","proper_motion_ra_mas_yr":-32.44,"proper_motion_dec_mas_yr":-31.12},"designations":[{"catalog":"HD","designation":"HD 28639"},{"catalog":"HIP","designation":"HIP 20965"}],"source":{"id":"hyg","name":"HYG Database v4.1","url":"https://github.com/astronexus/HYG-Database","license":"CC-BY-SA-4.0"},"updated_at":"2026-08-30T09:56:50.739Z","attribution":"Data from SpaceCatalog.org. Individual records carry their source and license in `source`; attribution is required for CC-BY and CC-BY-SA rows."}