{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.683","julian_year":2026.683,"time":"2026-09-07T08:00:19.005Z","years_from_j2000":26.683,"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-166866","name":"41 Dra","class":"k2vv_orange_dwarf","category":"star","object_type":"K2Vv orange dwarf","mag":5.74,"mag_band":"V","abs_mag":1.725,"abs_mag_band":"V","distance_ly":207.2149745165123,"distance_method":"parallax","ra_deg":270.03789,"dec_deg":80.004095,"epoch_ra_deg":269.535588,"epoch_dec_deg":80.002161,"epoch_moved_arcsec":3.538,"pm_ra_mas_yr":46.91,"pm_dec_mas_yr":124.03,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Draco","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-166866","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"18002+8000","companions":[{"measured":2012,"magnitude":6.69,"components":"Aa,Ab","discoverer_code":"BAG   6","separation_arcsec":0.1,"position_angle_deg":316},{"measured":2023,"magnitude":6,"components":"AB","discoverer_code":"STF2308","separation_arcsec":18.6,"position_angle_deg":232},{"measured":2017,"magnitude":8.34,"components":"AC","discoverer_code":"STF2308","separation_arcsec":225.3,"position_angle_deg":129}],"spectral_type":"K2Vv","uncertainties":{"metallicity_fe_h":[0.1,0.1]},"color_index_bv":0.516,"luminosity_solar":17.78279410038923,"metallicity_fe_h":-0.07,"variable_mag_max":5.452,"variable_mag_min":5.892,"radial_velocity_km_s":10,"spectral_type_source":"SIMBAD (quality C)","surface_gravity_log_g":3.7,"surface_temperature_k":6230,"metallicity_fe_h_source":"One spectroscopic determination, compiled from the literature (PASTEL, Soubiran+ 2016)","proper_motion_ra_mas_yr":46.91,"proper_motion_dec_mas_yr":124.03,"stellar_parameters_method":"Spectroscopic determinations compiled from the literature (PASTEL, Soubiran+ 2016)"},"designations":[{"catalog":"Bayer/Flamsteed","designation":"41 Dra"},{"catalog":"HD","designation":"HD 166866"},{"catalog":"HIP","designation":"HIP 88136"},{"catalog":"HR","designation":"HR 6810"}],"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."}