{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.684","julian_year":2026.684,"time":"2026-09-07T22:41:14.302Z","years_from_j2000":26.684,"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":"hip-15455","name":"HIP 15455","class":"f0_yellow_white_star","category":"star","object_type":"F0 yellow-white star","mag":9.68,"mag_band":"V","abs_mag":1.185,"abs_mag_band":"V","distance_ly":1630.781888583717,"distance_method":"parallax","ra_deg":49.82718,"dec_deg":45.951308,"epoch_ra_deg":50.288739,"epoch_dec_deg":46.049163,"epoch_moved_arcsec":0.225,"pm_ra_mas_yr":5.1,"pm_dec_mas_yr":6.72,"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/hip-15455","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"03193+4559","age_years":974915860,"companions":[{"measured":2017,"magnitude":10.58,"components":"AB","discoverer_code":"STF 372","separation_arcsec":7.7,"position_angle_deg":292},{"measured":2016,"magnitude":15,"components":"AH","discoverer_code":"ABH  20","separation_arcsec":7.8,"position_angle_deg":236},{"measured":2016,"magnitude":13.1,"components":"AD","discoverer_code":"ABH  20","separation_arcsec":43.4,"position_angle_deg":78},{"measured":2017,"magnitude":11.27,"components":"AC","discoverer_code":"STF 372","separation_arcsec":53.5,"position_angle_deg":76},{"measured":2016,"magnitude":14.71,"components":"AE","discoverer_code":"ABH  20","separation_arcsec":61.6,"position_angle_deg":154},{"measured":2016,"magnitude":15.53,"components":"AG","discoverer_code":"ABH  20","separation_arcsec":62.3,"position_angle_deg":261},{"measured":2016,"magnitude":14.29,"components":"AF","discoverer_code":"ABH  20","separation_arcsec":73.6,"position_angle_deg":351}],"mass_solar":1.725,"radius_solar":2.03,"spectral_type":"F0","color_index_bv":0.369,"luminosity_solar":29.241523778433354,"variable_mag_max":9.639,"variable_mag_min":9.849,"radial_velocity_km_s":0,"spectral_type_source":"SIMBAD (quality D)","surface_gravity_log_g":4.035,"surface_temperature_k":7635,"proper_motion_ra_mas_yr":5.1,"proper_motion_dec_mas_yr":6.72,"stellar_parameters_method":"Gaia DR3 model fit (GSP-Phot, FLAME; RUWE ≤ 1.4) — low confidence: above 7,500 K GSP-Phot's temperature and extinction are degenerate","bolometric_luminosity_solar":11.503},"designations":[{"catalog":"HIP","designation":"HIP 15455"}],"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."}