{"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":"2026-09-01T19:31:01.156Z","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":"hd-28355","name":"79 Tau","class":"ka5hf0vmf0_yellow_white_main_sequence_star","category":"star","object_type":"kA5hF0VmF0 yellow-white main-sequence star","mag":5.02,"mag_band":"V","abs_mag":1.576,"abs_mag_band":"V","distance_ly":159.3339136421835,"distance_method":"parallax","ra_deg":67.209015,"dec_deg":13.047602,"epoch_ra_deg":67.585652,"epoch_dec_deg":13.107069,"epoch_moved_arcsec":2.833,"pm_ra_mas_yr":105.17,"pm_dec_mas_yr":-15.08,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Taurus","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-28355","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"age_years":971260250,"mass_solar":1.885,"radius_solar":2.442,"spectral_type":"kA5hF0VmF0","uncertainties":{"metallicity_fe_h":[0.25,0.25]},"color_index_bv":0.215,"luminosity_solar":20.398583002685616,"metallicity_fe_h":0.35,"radial_velocity_km_s":33,"spectral_type_source":"SIMBAD (1968MmSAI..39...19I, quality C)","surface_gravity_log_g":3.877,"surface_temperature_k":7681,"metallicity_fe_h_source":"One spectroscopic determination, compiled from the literature (PASTEL, Soubiran+ 2016)","proper_motion_ra_mas_yr":105.17,"proper_motion_dec_mas_yr":-15.08,"stellar_parameters_method":"Gaia DR3 model fit (GSP-Phot, FLAME; RUWE ≤ 1.4) — low confidence: above 7,500 K GSP-Phot's temperature and extinction are degenerate; Gaia's classifier calls the source a binary, which GSP-Phot fitted as one star","bolometric_luminosity_solar":17.9484},"designations":[{"catalog":"Bayer/Flamsteed","designation":"79 Tau"},{"catalog":"HD","designation":"HD 28355"},{"catalog":"HIP","designation":"HIP 20901"},{"catalog":"HR","designation":"HR 1414"}],"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."}