{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.671","julian_year":2026.671,"time":"2026-09-02T21:46:06.193Z","years_from_j2000":26.671,"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-56540","name":"HD 56540","class":"a3ii_iiisi_white_bright_giant","category":"star","object_type":"A3II-IIISi white bright giant","mag":8.05,"mag_band":"V","abs_mag":null,"abs_mag_band":null,"distance_ly":null,"distance_method":null,"ra_deg":109.4358,"dec_deg":7.796071,"epoch_ra_deg":109.799128,"epoch_dec_deg":7.748065,"epoch_moved_arcsec":0.085,"pm_ra_mas_yr":-2.73,"pm_dec_mas_yr":1.65,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Canis Minor","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-56540","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"07177+0748","companions":[{"measured":2016,"magnitude":11.83,"components":null,"discoverer_code":"A  2858","separation_arcsec":4.3,"position_angle_deg":10}],"spectral_type":"A3II-IIISi","color_index_bv":-0.013,"radial_velocity_km_s":0,"spectral_type_source":"SIMBAD (2022ApJS..259...63S, quality C)","proper_motion_ra_mas_yr":-2.73,"proper_motion_dec_mas_yr":1.65},"designations":[{"catalog":"HD","designation":"HD 56540"},{"catalog":"HIP","designation":"HIP 35320"}],"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."}