{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.665","julian_year":2026.665,"time":"2026-09-01T01:24:45.814Z","years_from_j2000":26.665,"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":"menkent","name":"Menkent","class":"k0_iiib_orange_giant","category":"star","object_type":"K0-IIIb orange giant","mag":2.06,"mag_band":"V","abs_mag":0.78,"abs_mag_band":"V","distance_ly":58.82001962657066,"distance_method":"parallax","ra_deg":211.670925,"dec_deg":-36.369954,"epoch_ra_deg":212.066923,"epoch_dec_deg":-36.501946,"epoch_moved_arcsec":19.556,"pm_ra_mas_yr":-519.29,"pm_dec_mas_yr":-517.87,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Centaurus","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/menkent","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"14067-3622","companions":[{"measured":1891,"magnitude":14,"components":"AB","discoverer_code":"DUN 253","separation_arcsec":3,"position_angle_deg":180},{"measured":2010,"magnitude":14.3,"components":"AC","discoverer_code":"SEE 196","separation_arcsec":115.1,"position_angle_deg":82}],"wikidata_id":"Q14225","also_known_as":["Theta Centauri","θ Cen","θ Centauri"],"spectral_type":"K0-IIIb","uncertainties":{"metallicity_fe_h":[0.153,0.153]},"color_index_bv":1.011,"luminosity_solar":42.46195639463128,"metallicity_fe_h":0.04,"wikipedia_article":"Theta Centauri","radial_velocity_km_s":1.3,"spectral_type_source":"SIMBAD (1989ApJS...71..245K, quality C)","surface_gravity_log_g":2.84,"surface_temperature_k":4980,"metallicity_fe_h_source":"Median of 3 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":-519.29,"proper_motion_dec_mas_yr":-517.87,"stellar_parameters_method":"Spectroscopic determinations compiled from the literature (PASTEL, Soubiran+ 2016)"},"designations":[{"catalog":"Bayer/Flamsteed","designation":"5 Theta Cen"},{"catalog":"Common name","designation":"Menkent"},{"catalog":"Gliese","designation":"GJ 539"},{"catalog":"Gliese","designation":"Gl 539"},{"catalog":"HD","designation":"HD 123139"},{"catalog":"HIP","designation":"HIP 68933"},{"catalog":"HR","designation":"HR 5288"},{"catalog":"IRAS","designation":"IRAS 14037-3607"}],"source":{"id":"hyg","name":"HYG Database v4.1","url":"https://github.com/astronexus/HYG-Database","license":"CC-BY-SA-4.0"},"updated_at":"2026-08-30T09:56:50.739Z","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."}