{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.677","julian_year":2026.677,"time":"2026-09-05T03:55:12.593Z","years_from_j2000":26.677,"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-83394","name":"HD 83394","class":"k0_orange_star","category":"star","object_type":"K0 orange star","mag":7.44,"mag_band":"V","abs_mag":2.294,"abs_mag_band":"V","distance_ly":348.8304429392337,"distance_method":"parallax","ra_deg":144.996225,"dec_deg":53.496962,"epoch_ra_deg":145.457761,"epoch_dec_deg":53.374466,"epoch_moved_arcsec":3.527,"pm_ra_mas_yr":-8.67,"pm_dec_mas_yr":-131.91,"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/hd-83394","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"age_years":1754755900,"mass_solar":1.741,"radius_solar":4.465,"spectral_type":"K0","uncertainties":{"metallicity_fe_h":[0.029,0.029]},"color_index_bv":0.911,"luminosity_solar":10.529312128434393,"metallicity_fe_h":-0.22,"radial_velocity_km_s":0,"spectral_type_source":"SIMBAD (1993yCat.3135....0C, quality E)","surface_gravity_log_g":3.349,"surface_temperature_k":5188,"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":-8.67,"proper_motion_dec_mas_yr":-131.91,"stellar_parameters_method":"Gaia DR3 model fit (GSP-Phot, FLAME; RUWE ≤ 1.4)","bolometric_luminosity_solar":12.915},"designations":[{"catalog":"HD","designation":"HD 83394"},{"catalog":"HIP","designation":"HIP 47437"}],"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."}