{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.667","julian_year":2026.667,"time":"2026-09-01T11:38:57.602Z","years_from_j2000":26.667,"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-17907","name":"HD 17907","class":"b9v_blue_white_main_sequence_star","category":"star","object_type":"B9V blue-white main-sequence star","mag":7.11,"mag_band":"V","abs_mag":0.648,"abs_mag_band":"V","distance_ly":639.522206924947,"distance_method":"parallax","ra_deg":43.1652,"dec_deg":6.474815,"epoch_ra_deg":43.520896,"epoch_dec_deg":6.585008,"epoch_moved_arcsec":0.673,"pm_ra_mas_yr":21.86,"pm_dec_mas_yr":-12.6,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Cetus","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-17907","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"02527+0628","companions":[{"measured":2020,"magnitude":7.92,"components":null,"discoverer_code":"STF 323","separation_arcsec":2.7,"position_angle_deg":278}],"mass_solar":2.655,"radius_solar":2.251,"spectral_type":"B9V","color_index_bv":-0.005,"luminosity_solar":47.95125740813503,"radial_velocity_km_s":0,"spectral_type_source":"SIMBAD (quality D)","surface_gravity_log_g":4.021,"surface_temperature_k":10950,"proper_motion_ra_mas_yr":21.86,"proper_motion_dec_mas_yr":-12.6,"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":56.8142},"designations":[{"catalog":"HD","designation":"HD 17907"},{"catalog":"HIP","designation":"HIP 13408"}],"source":{"id":"hyg","name":"HYG Database v4.1","url":"https://github.com/astronexus/HYG-Database","license":"CC-BY-SA-4.0"},"updated_at":"2026-08-30T09:56:50.739Z","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."}