{"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":"2026-09-04T03:00:57.968Z","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-18282","name":"HD 18282","class":"f8_yellow_white_star","category":"star","object_type":"F8 yellow-white star","mag":9.01,"mag_band":"V","abs_mag":null,"abs_mag_band":null,"distance_ly":null,"distance_method":null,"ra_deg":44.441715,"dec_deg":44.524132,"epoch_ra_deg":44.888266,"epoch_dec_deg":44.632212,"epoch_moved_arcsec":1.421,"pm_ra_mas_yr":49.87,"pm_dec_mas_yr":18.77,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Perseus","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-18282","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"02578+4431","age_years":2017976800,"companions":[{"measured":2017,"magnitude":9.3,"components":"AB","discoverer_code":"STF 328","separation_arcsec":14.7,"position_angle_deg":306},{"measured":2015,"magnitude":11.82,"components":"AC","discoverer_code":"STF 328","separation_arcsec":46.2,"position_angle_deg":96},{"measured":2015,"magnitude":13.16,"components":"AD","discoverer_code":"B  9001","separation_arcsec":100,"position_angle_deg":117}],"mass_solar":1.652,"radius_solar":3.195,"spectral_type":"F8","color_index_bv":0.748,"variable_mag_max":8.849,"variable_mag_min":9.239,"radial_velocity_km_s":0,"spectral_type_source":"SIMBAD (1993yCat.3135....0C, quality E)","surface_gravity_log_g":3.601,"surface_temperature_k":6138,"proper_motion_ra_mas_yr":49.87,"proper_motion_dec_mas_yr":18.77,"stellar_parameters_method":"Gaia DR3 model fit (GSP-Phot, FLAME; RUWE ≤ 1.4)","bolometric_luminosity_solar":12.5222},"designations":[{"catalog":"HD","designation":"HD 18282"},{"catalog":"HIP","designation":"HIP 13804"}],"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."}