{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.666","julian_year":2026.666,"time":"2026-09-01T04:18:52.713Z","years_from_j2000":26.666,"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-9774","name":"40 Cas","class":"g7iii_iiib_yellow_giant","category":"star","object_type":"G7III-IIIb yellow giant","mag":5.28,"mag_band":"V","abs_mag":-0.458,"abs_mag_band":"V","distance_ly":458.08467556489984,"distance_method":"parallax","ra_deg":24.62889,"dec_deg":73.04004,"epoch_ra_deg":25.172874,"epoch_dec_deg":73.176483,"epoch_moved_arcsec":0.473,"pm_ra_mas_yr":-11.81,"pm_dec_mas_yr":-13.23,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Cassiopeia","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-9774","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"01385+7302","age_years":250622240,"companions":[{"measured":2010,"magnitude":11.74,"components":null,"discoverer_code":"HJ 2054","separation_arcsec":52.9,"position_angle_deg":236}],"mass_solar":3.499,"radius_solar":16.528,"spectral_type":"G7III-IIIb","uncertainties":{"metallicity_fe_h":[0.06,0.06]},"color_index_bv":0.972,"luminosity_solar":132.8005886243731,"metallicity_fe_h":-0.04,"radial_velocity_km_s":-5,"spectral_type_source":"SIMBAD (1989ApJS...71..245K, quality B)","surface_gravity_log_g":2.477,"surface_temperature_k":5030,"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":-11.81,"proper_motion_dec_mas_yr":-13.23,"stellar_parameters_method":"Gaia DR3 model fit (GSP-Phot, FLAME; RUWE ≤ 1.4)","bolometric_luminosity_solar":168.8283},"designations":[{"catalog":"Bayer/Flamsteed","designation":"40 Cas"},{"catalog":"HD","designation":"HD 9774"},{"catalog":"HIP","designation":"HIP 7650"},{"catalog":"HR","designation":"HR 456"}],"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."}