{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.681","julian_year":2026.681,"time":"2026-09-06T20:30:44.333Z","years_from_j2000":26.681,"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-222794","name":"HD 222794","class":"g2v_yellow_main_sequence_star","category":"star","object_type":"G2V yellow main-sequence star","mag":7.14,"mag_band":"V","abs_mag":3.832,"abs_mag_band":"V","distance_ly":149.6131489607137,"distance_method":"parallax","ra_deg":355.86183,"dec_deg":58.080297,"epoch_ra_deg":356.191159,"epoch_dec_deg":58.232911,"epoch_moved_arcsec":16.527,"pm_ra_mas_yr":390.05,"pm_dec_mas_yr":481.19,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Cassiopeia","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-222794","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"23435+5805","age_years":9357739000,"companions":[{"measured":1993,"magnitude":null,"components":"Aa,Ab","discoverer_code":"CHR 120","separation_arcsec":0.1,"position_angle_deg":105},{"measured":2015,"magnitude":14.5,"components":"AP","discoverer_code":"FYM 149","separation_arcsec":70.5,"position_angle_deg":206},{"measured":2015,"magnitude":13.15,"components":"AI","discoverer_code":"FYM 149","separation_arcsec":112.6,"position_angle_deg":201},{"measured":2017,"magnitude":10.77,"components":"AC","discoverer_code":"ENG  88","separation_arcsec":146.7,"position_angle_deg":165},{"measured":2017,"magnitude":10.9,"components":"AE","discoverer_code":"ENG  88","separation_arcsec":167.4,"position_angle_deg":147},{"measured":2017,"magnitude":10.55,"components":"AB","discoverer_code":"ENG  88","separation_arcsec":170.6,"position_angle_deg":215},{"measured":2012,"magnitude":12.24,"components":"AG","discoverer_code":"TOB 231","separation_arcsec":194.9,"position_angle_deg":139},{"measured":2012,"magnitude":13.15,"components":"AM","discoverer_code":"FYM 149","separation_arcsec":195,"position_angle_deg":94},{"measured":2012,"magnitude":12.71,"components":"AL","discoverer_code":"FYM 149","separation_arcsec":204.5,"position_angle_deg":240},{"measured":2015,"magnitude":12.77,"components":"AQ","discoverer_code":"FYM 149","separation_arcsec":208.7,"position_angle_deg":267},{"measured":2017,"magnitude":9.8,"components":"AD","discoverer_code":"ENG  88","separation_arcsec":228.9,"position_angle_deg":198},{"measured":2012,"magnitude":13.02,"components":"AK","discoverer_code":"FYM 149","separation_arcsec":236,"position_angle_deg":162},{"measured":2017,"magnitude":9.03,"components":"AF","discoverer_code":"ENG  88","separation_arcsec":281,"position_angle_deg":197}],"mass_solar":1.047,"radius_solar":1.725,"spectral_type":"G2V","uncertainties":{"metallicity_fe_h":[0.072,0.072]},"color_index_bv":0.645,"luminosity_solar":2.553877135779322,"metallicity_fe_h":-0.76,"radial_velocity_km_s":-70.6,"spectral_type_source":"SIMBAD (1955ApJS....2..195R, quality C)","surface_gravity_log_g":4.092,"surface_temperature_k":5552,"metallicity_fe_h_source":"Median of 7 spectroscopic determinations in 8 papers, compiled from the literature (PASTEL, Soubiran+ 2016); the error bar is the scatter between them","proper_motion_ra_mas_yr":390.05,"proper_motion_dec_mas_yr":481.19,"stellar_parameters_method":"Gaia DR3 model fit (GSP-Phot, FLAME; RUWE ≤ 1.4)","bolometric_luminosity_solar":2.5567},"designations":[{"catalog":"HD","designation":"HD 222794"},{"catalog":"HIP","designation":"HIP 117029"}],"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."}