{"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":"2026-09-07T07:38:28.274Z","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-175740","name":"HD 175740","class":"g8iii_yellow_giant","category":"star","object_type":"G8III yellow giant","mag":5.46,"mag_band":"V","abs_mag":0.892,"abs_mag_band":"V","distance_ly":267.3412504358385,"distance_method":"parallax","ra_deg":283.71741000000003,"dec_deg":41.602723,"epoch_ra_deg":283.932114,"epoch_dec_deg":41.636215,"epoch_moved_arcsec":0.071,"pm_ra_mas_yr":-1.37,"pm_dec_mas_yr":-2.3,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Lyra","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-175740","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"18549+4136","companions":[{"measured":2013,"magnitude":12.6,"components":"AB","discoverer_code":"HO  270","separation_arcsec":8.4,"position_angle_deg":300},{"measured":2016,"magnitude":11.5,"components":"AC","discoverer_code":"HO  270","separation_arcsec":23.9,"position_angle_deg":39}],"spectral_type":"G8III","uncertainties":{"metallicity_fe_h":[0.076,0.076]},"color_index_bv":1.034,"luminosity_solar":38.30010812264485,"metallicity_fe_h":0.075,"radial_velocity_km_s":-9,"spectral_type_source":"SIMBAD (1990ApJS...74.1075M, quality D)","surface_gravity_log_g":2.81,"surface_temperature_k":4788,"metallicity_fe_h_source":"Median of 6 spectroscopic determinations in 5 papers, compiled from the literature (PASTEL, Soubiran+ 2016); the error bar is the scatter between them","proper_motion_ra_mas_yr":-1.37,"proper_motion_dec_mas_yr":-2.3,"stellar_parameters_method":"Spectroscopic determinations compiled from the literature (PASTEL, Soubiran+ 2016)"},"designations":[{"catalog":"HD","designation":"HD 175740"},{"catalog":"HIP","designation":"HIP 92831"},{"catalog":"HR","designation":"HR 7146"}],"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."}