{"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":"2026-08-31T22:34:19.412Z","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":"phecda","name":"Phecda","class":"a0v_white_main_sequence_star","category":"star","object_type":"A0V white main-sequence star","mag":2.41,"mag_band":"V","abs_mag":0.377,"abs_mag_band":"V","distance_ly":83.18194410374508,"distance_method":"parallax","ra_deg":178.45752000000002,"dec_deg":53.69476,"epoch_ra_deg":178.810824,"epoch_dec_deg":53.545483,"epoch_moved_arcsec":2.889,"pm_ra_mas_yr":107.76,"pm_dec_mas_yr":11.16,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Ursa Major","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/phecda","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wikidata_id":"Q13099","also_known_as":["Gamma Ursae Majoris","The Celestial Shining Pearl","γ UMa","γ Ursae Majoris"],"spectral_type":"A0V","color_index_bv":0.044,"luminosity_solar":61.54602373713163,"wikipedia_article":"Phecda","radial_velocity_km_s":-13,"spectral_type_source":"SIMBAD (2024A&A...690A.176N, quality C)","surface_temperature_k":9350,"proper_motion_ra_mas_yr":107.76,"proper_motion_dec_mas_yr":11.16,"stellar_parameters_method":"Spectroscopic determinations compiled from the literature (PASTEL, Soubiran+ 2016)"},"designations":[{"catalog":"Bayer/Flamsteed","designation":"64 Gamma UMa"},{"catalog":"Common name","designation":"Phecda"},{"catalog":"HD","designation":"HD 103287"},{"catalog":"HIP","designation":"HIP 58001"},{"catalog":"HR","designation":"HR 4554"},{"catalog":"IRAS","designation":"IRAS 11512+5358"}],"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."}