{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.671","julian_year":2026.671,"time":"2026-09-03T06:18:11.499Z","years_from_j2000":26.671,"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-50573","name":"HD 50573","class":"f8_g0v_yellow_white_main_sequence_star","category":"star","object_type":"F8/G0V yellow-white main-sequence star","mag":9.49,"mag_band":"V","abs_mag":3.857,"abs_mag_band":"V","distance_ly":436.6216289728718,"distance_method":"parallax","ra_deg":100.49904000000001,"dec_deg":-79.608777,"epoch_ra_deg":100.037763,"epoch_dec_deg":-79.632481,"epoch_moved_arcsec":2.456,"pm_ra_mas_yr":-0.81,"pm_dec_mas_yr":92.09,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Mensa","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-50573","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"age_years":4631139000,"mass_solar":1.246,"radius_solar":2.076,"spectral_type":"F8/G0V","color_index_bv":0.633,"luminosity_solar":2.495743794831569,"radial_velocity_km_s":0,"spectral_type_source":"SIMBAD (1975MSS...C01....0H, quality D)","surface_gravity_log_g":3.824,"surface_temperature_k":5920,"proper_motion_ra_mas_yr":-0.81,"proper_motion_dec_mas_yr":92.09,"stellar_parameters_method":"Gaia DR3 model fit (GSP-Phot, FLAME; RUWE ≤ 1.4)","bolometric_luminosity_solar":4.6099},"designations":[{"catalog":"HD","designation":"HD 50573"},{"catalog":"HIP","designation":"HIP 32068"}],"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."}