{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.672","julian_year":2026.672,"time":"2026-09-03T08:56:45.793Z","years_from_j2000":26.672,"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-99687","name":"HD 99687","class":"f8_yellow_white_star","category":"star","object_type":"F8 yellow-white star","mag":8.42,"mag_band":"V","abs_mag":3.954,"abs_mag_band":"V","distance_ly":255.00895163799072,"distance_method":"parallax","ra_deg":172.574955,"dec_deg":81.037305,"epoch_ra_deg":173.052455,"epoch_dec_deg":80.889489,"epoch_moved_arcsec":1.156,"pm_ra_mas_yr":32.68,"pm_dec_mas_yr":28.45,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Camelopardalis","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-99687","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"11303+8102","age_years":2918037200,"companions":[{"measured":2016,"magnitude":9.85,"components":null,"discoverer_code":"STF1539","separation_arcsec":19.4,"position_angle_deg":313}],"mass_solar":1.146,"radius_solar":1.214,"spectral_type":"F8","color_index_bv":0.538,"luminosity_solar":2.2824433121735033,"variable_mag_max":8.311,"variable_mag_min":8.501,"radial_velocity_km_s":0,"spectral_type_source":"SIMBAD (1993yCat.3135....0C, quality E)","surface_gravity_log_g":4.258,"surface_temperature_k":6173,"proper_motion_ra_mas_yr":32.68,"proper_motion_dec_mas_yr":28.45,"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":1.9193},"designations":[{"catalog":"HD","designation":"HD 99687"},{"catalog":"HIP","designation":"HIP 56123"}],"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."}