{"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":"2026-09-02T22:39:08.067Z","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-84645","name":"HD 84645","class":"f2v_yellow_white_main_sequence_star","category":"star","object_type":"F2V yellow-white main-sequence star","mag":9.01,"mag_band":"V","abs_mag":1.583,"abs_mag_band":"V","distance_ly":997.4201233210839,"distance_method":"parallax","ra_deg":146.22142499999998,"dec_deg":-55.091403,"epoch_ra_deg":146.443778,"epoch_dec_deg":-55.21457,"epoch_moved_arcsec":0.239,"pm_ra_mas_yr":7.62,"pm_dec_mas_yr":-4.72,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Vela","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-84645","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"09449-5505","age_years":1269321600,"companions":[{"measured":2010,"magnitude":10.56,"components":null,"discoverer_code":"HDS1406","separation_arcsec":19.4,"position_angle_deg":281}],"mass_solar":1.823,"radius_solar":2.868,"spectral_type":"F2V","color_index_bv":0.387,"luminosity_solar":20.267491520989655,"variable_mag_max":8.889,"variable_mag_min":9.079,"radial_velocity_km_s":0,"spectral_type_source":"SIMBAD (1975MSS...C01....0H, quality C)","surface_gravity_log_g":3.729,"surface_temperature_k":6940,"proper_motion_ra_mas_yr":7.62,"proper_motion_dec_mas_yr":-4.72,"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":16.6594},"designations":[{"catalog":"HD","designation":"HD 84645"},{"catalog":"HIP","designation":"HIP 47821"}],"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."}