{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.654","julian_year":2026.654,"time":"2026-08-27T19:58:10.783Z","years_from_j2000":26.654,"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-9540","name":"HD 9540","class":"k0v_orange_dwarf","category":"star","object_type":"K0V orange dwarf","mag":6.97,"mag_band":"V","abs_mag":5.57,"abs_mag_band":"V","distance_ly":62.13670383157223,"distance_method":"parallax","ra_deg":23.315805,"dec_deg":-24.177962,"epoch_ra_deg":23.636261,"epoch_dec_deg":-24.041148,"epoch_moved_arcsec":8.401,"pm_ra_mas_yr":271.86,"pm_dec_mas_yr":-159.5,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Cetus","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-9540","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"01333-2411","age_years":4516621000,"companions":[{"measured":2015,"magnitude":12.77,"components":"AB","discoverer_code":"LDS2209","separation_arcsec":335.9,"position_angle_deg":220}],"mass_solar":0.903,"radius_solar":0.85,"spectral_type":"K0V","uncertainties":{"metallicity_fe_h":[0.01,0.01]},"color_index_bv":0.766,"luminosity_solar":0.5152286445817562,"metallicity_fe_h":-0.03,"radial_velocity_km_s":-49.1,"spectral_type_source":"SIMBAD (1988MSS...C04....0H, quality C)","surface_gravity_log_g":4.492,"surface_temperature_k":5376,"metallicity_fe_h_source":"Median of 2 spectroscopic determinations in 3 papers, compiled from the literature (PASTEL, Soubiran+ 2016); the error bar is the scatter between them","proper_motion_ra_mas_yr":271.86,"proper_motion_dec_mas_yr":-159.5,"stellar_parameters_method":"Gaia DR3 model fit (GSP-Phot, FLAME; RUWE ≤ 1.4)","bolometric_luminosity_solar":0.5441},"designations":[{"catalog":"Gliese","designation":"Gl 59A"},{"catalog":"HD","designation":"HD 9540"},{"catalog":"HIP","designation":"HIP 7235"}],"source":{"id":"hyg","name":"HYG Database v4.1","url":"https://github.com/astronexus/HYG-Database","license":"CC-BY-SA-4.0"},"updated_at":"2026-08-27T19:16:43.430Z","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."}