{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.666","julian_year":2026.666,"time":"2026-09-01T01:56:35.530Z","years_from_j2000":26.666,"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-252109","name":"HD 252109","class":"f0_yellow_white_star","category":"star","object_type":"F0 yellow-white star","mag":9.61,"mag_band":"V","abs_mag":1.211,"abs_mag_band":"V","distance_ly":1560.5568327411474,"distance_method":"parallax","ra_deg":92.102955,"dec_deg":22.998059,"epoch_ra_deg":92.510374,"epoch_dec_deg":22.994305,"epoch_moved_arcsec":0.218,"pm_ra_mas_yr":3.16,"pm_dec_mas_yr":-7.55,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Gemini","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-252109","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"age_years":771656450,"mass_solar":2.302,"radius_solar":4.869,"spectral_type":"F0","color_index_bv":0.337,"luminosity_solar":28.54959816900407,"radial_velocity_km_s":0,"spectral_type_source":"SIMBAD (1993yCat.3135....0C, quality E)","surface_gravity_log_g":3.438,"surface_temperature_k":7262,"proper_motion_ra_mas_yr":3.16,"proper_motion_dec_mas_yr":-7.55,"stellar_parameters_method":"Gaia DR3 model fit (GSP-Phot, FLAME; RUWE ≤ 1.4)","bolometric_luminosity_solar":52.0844},"designations":[{"catalog":"HD","designation":"HD 252109"},{"catalog":"HIP","designation":"HIP 29117"}],"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."}