{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.667","julian_year":2026.667,"time":"2026-09-01T16:12:11.589Z","years_from_j2000":26.667,"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-181558","name":"V4199 Sgr","class":"b5iii_blue_white_giant","category":"star","object_type":"B5III blue-white giant","mag":6.25,"mag_band":"V","abs_mag":-0.649,"abs_mag_band":"V","distance_ly":782.1497385877235,"distance_method":"parallax","ra_deg":290.404635,"dec_deg":-19.234446,"epoch_ra_deg":290.797658,"epoch_dec_deg":-19.184107,"epoch_moved_arcsec":0.306,"pm_ra_mas_yr":0.8,"pm_dec_mas_yr":-11.46,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Sagittarius","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-181558","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"19216-1914","companions":[{"measured":2000,"magnitude":13.3,"components":"AB","discoverer_code":"BU 1467","separation_arcsec":48.9,"position_angle_deg":157},{"measured":2003,"magnitude":9.96,"components":"AC","discoverer_code":"H 6 120","separation_arcsec":90.9,"position_angle_deg":310}],"mass_solar":3.804,"radius_solar":3.424,"spectral_type":"B5III","color_index_bv":-0.091,"luminosity_solar":158.34341239145746,"variable_mag_max":6.216,"variable_mag_min":6.276,"radial_velocity_km_s":-23,"spectral_type_source":"SIMBAD (1988MSS...C04....0H, quality C)","variable_designation":"V4199 Sgr","surface_gravity_log_g":3.966,"surface_temperature_k":12916,"proper_motion_ra_mas_yr":0.8,"proper_motion_dec_mas_yr":-11.46,"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","bolometric_luminosity_solar":297.8348},"designations":[{"catalog":"HD","designation":"HD 181558"},{"catalog":"HIP","designation":"HIP 95159"},{"catalog":"HR","designation":"HR 7339"},{"catalog":"Variable star","designation":"V4199 Sgr"}],"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."}