{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.679","julian_year":2026.679,"time":"2026-09-05T23:56:53.962Z","years_from_j2000":26.679,"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-196180","name":"4 ζ Del","class":"a3va_white_main_sequence_star","category":"star","object_type":"A3Va white main-sequence star","mag":4.64,"mag_band":"V","abs_mag":0.494,"abs_mag_band":"V","distance_ly":220.07858205366065,"distance_method":"parallax","ra_deg":308.82723,"dec_deg":14.674213,"epoch_ra_deg":309.140836,"epoch_dec_deg":14.766601,"epoch_moved_arcsec":1.243,"pm_ra_mas_yr":45.08,"pm_dec_mas_yr":11.71,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Delphinus","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-196180","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"20353+1440","companions":[{"measured":2013,"magnitude":15.3,"components":null,"discoverer_code":"DRS  32","separation_arcsec":13.5,"position_angle_deg":143}],"spectral_type":"A3Va","color_index_bv":0.12,"luminosity_solar":55.25861556300781,"metallicity_fe_h":-0.05,"radial_velocity_km_s":-25,"spectral_type_source":"SIMBAD (1989ApJS...70..623G, quality C)","surface_gravity_log_g":3.72,"surface_temperature_k":8346,"metallicity_fe_h_source":"One spectroscopic determination, compiled from the literature (PASTEL, Soubiran+ 2016)","proper_motion_ra_mas_yr":45.08,"proper_motion_dec_mas_yr":11.71,"stellar_parameters_method":"Spectroscopic determinations compiled from the literature (PASTEL, Soubiran+ 2016)"},"designations":[{"catalog":"Bayer/Flamsteed","designation":"4 Zeta Del"},{"catalog":"HD","designation":"HD 196180"},{"catalog":"HIP","designation":"HIP 101589"},{"catalog":"HR","designation":"HR 7871"}],"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."}