{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.668","julian_year":2026.668,"time":"2026-09-02T03:36:14.331Z","years_from_j2000":26.668,"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":"muphrid","name":"Muphrid","class":"g0iv_yellow_subgiant","category":"star","object_type":"G0IV yellow subgiant","mag":2.68,"mag_band":"V","abs_mag":2.396,"abs_mag_band":"V","distance_ly":37.16878080460008,"distance_method":"parallax","ra_deg":208.671165,"dec_deg":18.397717,"epoch_ra_deg":208.991481,"epoch_dec_deg":18.263009,"epoch_moved_arcsec":9.687,"pm_ra_mas_yr":-60.95,"pm_dec_mas_yr":-358.1,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Boötes","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/muphrid","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"13547+1824","companions":[{"measured":2023,"magnitude":9.99,"components":null,"discoverer_code":"SHJ 169","separation_arcsec":114.3,"position_angle_deg":85}],"spectral_type":"G0IV","uncertainties":{"metallicity_fe_h":[0.072,0.072]},"color_index_bv":0.58,"luminosity_solar":9.585173976856456,"metallicity_fe_h":0.27,"radial_velocity_km_s":1,"spectral_type_source":"SIMBAD (1989ApJS...71..245K, quality B)","surface_gravity_log_g":3.8,"surface_temperature_k":6048,"metallicity_fe_h_source":"Median of 22 spectroscopic determinations in 27 papers, compiled from the literature (PASTEL, Soubiran+ 2016); the error bar is the scatter between them","proper_motion_ra_mas_yr":-60.95,"proper_motion_dec_mas_yr":-358.1,"stellar_parameters_method":"Spectroscopic determinations compiled from the literature (PASTEL, Soubiran+ 2016)"},"designations":[{"catalog":"Bayer/Flamsteed","designation":"8 Eta Boo"},{"catalog":"Common name","designation":"Muphrid"},{"catalog":"Gliese","designation":"Gl 534"},{"catalog":"HD","designation":"HD 121370"},{"catalog":"HIP","designation":"HIP 67927"},{"catalog":"HR","designation":"HR 5235"}],"source":{"id":"hyg","name":"HYG Database v4.1","url":"https://github.com/astronexus/HYG-Database","license":"CC-BY-SA-4.0"},"updated_at":"2026-09-01T22:58:55.274Z","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."}