{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.687","julian_year":2026.687,"time":"2026-09-08T23:57:13.319Z","years_from_j2000":26.687,"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-223047","name":"20 ψ And","class":"g3ib_ii_yellow_supergiant","category":"star","object_type":"G3Ib-II yellow supergiant","mag":4.97,"mag_band":"V","abs_mag":-2.471,"abs_mag_band":"V","distance_ly":1003.5580601933352,"distance_method":"parallax","ra_deg":356.50851,"dec_deg":46.420276,"epoch_ra_deg":356.841335,"epoch_dec_deg":46.569446,"epoch_moved_arcsec":0.294,"pm_ra_mas_yr":9.05,"pm_dec_mas_yr":-6.25,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Andromeda","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-223047","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"23460+4625","companions":[{"measured":2003,"magnitude":null,"components":"Aa,Ab","discoverer_code":"MCA  75","separation_arcsec":0.2,"position_angle_deg":164},{"measured":2018,"magnitude":8.11,"components":"Aa,Ac","discoverer_code":"MCA  75","separation_arcsec":0.4,"position_angle_deg":275},{"measured":2015,"magnitude":14.6,"components":"AB","discoverer_code":"BU 1532","separation_arcsec":24.8,"position_angle_deg":218},{"measured":2015,"magnitude":13.1,"components":"AC","discoverer_code":"BU 1532","separation_arcsec":61.9,"position_angle_deg":16},{"measured":2015,"magnitude":9.46,"components":"AD","discoverer_code":"BU 1532","separation_arcsec":186.9,"position_angle_deg":152},{"measured":2015,"magnitude":10.38,"components":"AE","discoverer_code":"ARN  27","separation_arcsec":240.6,"position_angle_deg":318}],"spectral_type":"G3Ib-II","uncertainties":{"metallicity_fe_h":[0.01,0.01]},"color_index_bv":1.086,"luminosity_solar":848.0080988896916,"metallicity_fe_h":0.105,"radial_velocity_km_s":-25,"spectral_type_source":"SIMBAD (1989ApJS...71..245K, quality C)","surface_gravity_log_g":1.47,"surface_temperature_k":4847,"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":9.05,"proper_motion_dec_mas_yr":-6.25,"stellar_parameters_method":"Spectroscopic determinations compiled from the literature (PASTEL, Soubiran+ 2016)"},"designations":[{"catalog":"Bayer/Flamsteed","designation":"20 Psi And"},{"catalog":"HD","designation":"HD 223047"},{"catalog":"HIP","designation":"HIP 117221"},{"catalog":"HR","designation":"HR 9003"}],"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."}