{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.672","julian_year":2026.672,"time":"2026-09-03T13:35:14.390Z","years_from_j2000":26.672,"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-139477","name":"HD 139477","class":"k3v_orange_dwarf","category":"star","object_type":"K3V orange dwarf","mag":8.39,"mag_band":"V","abs_mag":6.984,"abs_mag_band":"V","distance_ly":62.31478521380556,"distance_method":"parallax","ra_deg":233.833095,"dec_deg":60.086992,"epoch_ra_deg":233.972487,"epoch_dec_deg":59.995859,"epoch_moved_arcsec":6.323,"pm_ra_mas_yr":172.22,"pm_dec_mas_yr":-162.88,"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-139477","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"15353+6005","companions":[{"measured":2017,"magnitude":17.2,"components":"AC","discoverer_code":"HLA  12","separation_arcsec":4,"position_angle_deg":314},{"measured":2016,"magnitude":13.4,"components":"AB","discoverer_code":"LDS2723","separation_arcsec":42.5,"position_angle_deg":98}],"radius_solar":0.75,"spectral_type":"K3V","uncertainties":{"metallicity_fe_h":[0.12,0.12]},"color_index_bv":1.063,"luminosity_solar":0.14008769839545832,"metallicity_fe_h":-0.01,"radial_velocity_km_s":0,"spectral_type_source":"SIMBAD (1998PASP..110..268L, quality C)","surface_gravity_log_g":4.553,"surface_temperature_k":4534,"metallicity_fe_h_source":"Median of 2 spectroscopic determinations in 2 papers, compiled from the literature (PASTEL, Soubiran+ 2016); the error bar is the scatter between them","proper_motion_ra_mas_yr":172.22,"proper_motion_dec_mas_yr":-162.88,"stellar_parameters_method":"Gaia DR3 model fit (GSP-Phot, FLAME; RUWE ≤ 1.4)","bolometric_luminosity_solar":0.2136},"designations":[{"catalog":"HD","designation":"HD 139477"},{"catalog":"HIP","designation":"HIP 76315"}],"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."}