{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.680","julian_year":2026.68,"time":"2026-09-06T07:34:17.320Z","years_from_j2000":26.68,"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-188650","name":"HD 188650","class":"g1ib_iich2fe_1_yellow_supergiant","category":"star","object_type":"G1Ib-IICH2Fe-1 yellow supergiant","mag":5.79,"mag_band":"V","abs_mag":-2.045,"abs_mag_band":"V","distance_ly":1203.5291015607586,"distance_method":"parallax","ra_deg":298.70104499999997,"dec_deg":36.995676,"epoch_ra_deg":298.945666,"epoch_dec_deg":37.065834,"epoch_moved_arcsec":0.375,"pm_ra_mas_yr":11.16,"pm_dec_mas_yr":8.54,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Cygnus","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-188650","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"spectral_type":"G1Ib-IICH2Fe-1","uncertainties":{"metallicity_fe_h":[0.1,0.1]},"color_index_bv":0.773,"luminosity_solar":572.7960309858292,"metallicity_fe_h":-0.77,"radial_velocity_km_s":-24,"spectral_type_source":"SIMBAD (1989ApJS...71..245K, quality B)","surface_gravity_log_g":1.99,"surface_temperature_k":5450,"metallicity_fe_h_source":"Median of 2 spectroscopic determinations in 3 papers, compiled from the literature (PASTEL, Soubiran+ 2016); the error bar is the scatter between them","proper_motion_ra_mas_yr":11.16,"proper_motion_dec_mas_yr":8.54,"stellar_parameters_method":"Spectroscopic determinations compiled from the literature (PASTEL, Soubiran+ 2016)"},"designations":[{"catalog":"HD","designation":"HD 188650"},{"catalog":"HIP","designation":"HIP 97985"},{"catalog":"HR","designation":"HR 7606"}],"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."}