{"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":"2026-09-04T03:03:42.694Z","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-128299","name":"HD 128299","class":"f2v_yellow_white_main_sequence_star","category":"star","object_type":"F2V yellow-white main-sequence star","mag":8.2,"mag_band":"V","abs_mag":2.169,"abs_mag_band":"V","distance_ly":524.3671531136296,"distance_method":"parallax","ra_deg":219.26443500000002,"dec_deg":-33.179636,"epoch_ra_deg":219.669367,"epoch_dec_deg":-33.296652,"epoch_moved_arcsec":0.949,"pm_ra_mas_yr":-29.74,"pm_dec_mas_yr":-19.5,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Centaurus","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-128299","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"age_years":1424155500,"mass_solar":1.744,"radius_solar":2.609,"spectral_type":"F2V","color_index_bv":0.438,"luminosity_solar":11.81408251920887,"radial_velocity_km_s":0,"spectral_type_source":"SIMBAD (1982MSS...C03....0H, quality C)","surface_gravity_log_g":3.76,"surface_temperature_k":6823,"proper_motion_ra_mas_yr":-29.74,"proper_motion_dec_mas_yr":-19.5,"stellar_parameters_method":"Gaia DR3 model fit (GSP-Phot, FLAME; RUWE ≤ 1.4) — low confidence: Gaia's classifier calls the source a binary, which GSP-Phot fitted as one star","bolometric_luminosity_solar":13.6026},"designations":[{"catalog":"HD","designation":"HD 128299"},{"catalog":"HIP","designation":"HIP 71477"}],"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."}