{"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":"2026-09-03T02:04:57.844Z","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-207129","name":"HD 207129","class":"g2v_yellow_main_sequence_star","category":"star","object_type":"G2V yellow main-sequence star","mag":5.57,"mag_band":"V","abs_mag":4.55,"abs_mag_band":"V","distance_ly":52.168386459415395,"distance_method":"parallax","ra_deg":327.06544499999995,"dec_deg":-47.303615,"epoch_ra_deg":327.50076,"epoch_dec_deg":-47.181275,"epoch_moved_arcsec":9.023,"pm_ra_mas_yr":165.64,"pm_dec_mas_yr":-295,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Grus","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-207129","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"21483-4718","age_years":6902565000,"companions":[{"measured":2013,"magnitude":8.76,"components":null,"discoverer_code":"BSO  15","separation_arcsec":79,"position_angle_deg":350}],"mass_solar":0.996,"radius_solar":1.083,"spectral_type":"G2V","uncertainties":{"metallicity_fe_h":[0.066,0.066]},"color_index_bv":0.601,"luminosity_solar":1.318256738556407,"metallicity_fe_h":-0.005,"radial_velocity_km_s":-6.5,"spectral_type_source":"SIMBAD (2006A&A...460..695T, quality C)","surface_gravity_log_g":4.295,"surface_temperature_k":5816,"metallicity_fe_h_source":"Median of 12 spectroscopic determinations in 12 papers, compiled from the literature (PASTEL, Soubiran+ 2016); the error bar is the scatter between them","proper_motion_ra_mas_yr":165.64,"proper_motion_dec_mas_yr":-295,"stellar_parameters_method":"Gaia DR3 model fit (GSP-Phot, FLAME; RUWE ≤ 1.4)","bolometric_luminosity_solar":1.2148},"designations":[{"catalog":"Gliese","designation":"Gl 838"},{"catalog":"HD","designation":"HD 207129"},{"catalog":"HIP","designation":"HIP 107649"},{"catalog":"HR","designation":"HR 8323"}],"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."}