{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.674","julian_year":2026.674,"time":"2026-09-04T08:29:54.498Z","years_from_j2000":26.674,"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-184448","name":"HD 184448","class":"f8_yellow_white_star","category":"star","object_type":"F8 yellow-white star","mag":8.05,"mag_band":"V","abs_mag":4.528,"abs_mag_band":"V","distance_ly":165.14243257294098,"distance_method":"parallax","ra_deg":293.01066000000003,"dec_deg":50.181545,"epoch_ra_deg":293.187489,"epoch_dec_deg":50.240257,"epoch_moved_arcsec":8.163,"pm_ra_mas_yr":-90.99,"pm_dec_mas_yr":292.17,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Cygnus","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-184448","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"19320+5011","age_years":12862900000,"companions":[{"measured":2016,"magnitude":13.77,"components":null,"discoverer_code":"KPP3342","separation_arcsec":4.2,"position_angle_deg":57}],"mass_solar":0.934,"radius_solar":1.24,"spectral_type":"F8","uncertainties":{"metallicity_fe_h":[0.105,0.105]},"color_index_bv":0.659,"luminosity_solar":1.345240705148632,"metallicity_fe_h":-0.325,"radial_velocity_km_s":-21.9,"spectral_type_source":"SIMBAD (1999MNRAS.302...22C, quality D)","surface_gravity_log_g":4.28,"surface_temperature_k":5633,"metallicity_fe_h_source":"Median of 2 spectroscopic determinations in 3 papers, compiled from the literature (PASTEL, Soubiran+ 2016); the error bar is the scatter between them","proper_motion_ra_mas_yr":-90.99,"proper_motion_dec_mas_yr":292.17,"stellar_parameters_method":"Gaia DR3 model fit (GSP-Phot, FLAME; RUWE ≤ 1.4)","bolometric_luminosity_solar":1.3892},"designations":[{"catalog":"HD","designation":"HD 184448"},{"catalog":"HIP","designation":"HIP 96077"}],"source":{"id":"hyg","name":"HYG Database v4.1","url":"https://github.com/astronexus/HYG-Database","license":"CC-BY-SA-4.0"},"updated_at":"2026-09-02T19:50:56.720Z","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."}