{"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":"2026-09-06T07:12:39.421Z","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-221356","name":"HD 221356","class":"f7v_yellow_white_main_sequence_star","category":"star","object_type":"F7V yellow-white main-sequence star","mag":6.5,"mag_band":"V","abs_mag":4.415,"abs_mag_band":"V","distance_ly":85.18063038639329,"distance_method":"parallax","ra_deg":352.881255,"dec_deg":-4.087406,"epoch_ra_deg":353.228207,"epoch_dec_deg":-3.940655,"epoch_moved_arcsec":7.012,"pm_ra_mas_yr":178.65,"pm_dec_mas_yr":-192.79,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Aquarius","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-221356","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"23315-0405","age_years":4214114700,"companions":[{"measured":2010,"magnitude":20.5,"components":"A,BC","discoverer_code":"KO    3","separation_arcsec":451.1,"position_angle_deg":262}],"mass_solar":1.063,"radius_solar":1.114,"spectral_type":"F7V","uncertainties":{"metallicity_fe_h":[0.043,0.043]},"color_index_bv":0.531,"luminosity_solar":1.4927944095789956,"metallicity_fe_h":-0.23,"radial_velocity_km_s":-13.1,"spectral_type_source":"SIMBAD (1999MSS...C05....0H, quality C)","surface_gravity_log_g":4.268,"surface_temperature_k":5969,"metallicity_fe_h_source":"Median of 10 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":178.65,"proper_motion_dec_mas_yr":-192.79,"stellar_parameters_method":"Gaia DR3 model fit (GSP-Phot, FLAME; RUWE ≤ 1.4)","bolometric_luminosity_solar":1.4113},"designations":[{"catalog":"Gliese","designation":"GJ 9829"},{"catalog":"HD","designation":"HD 221356"},{"catalog":"HIP","designation":"HIP 116106"},{"catalog":"HR","designation":"HR 8931"}],"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."}