{"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":"2026-08-27T21:07:11.579Z","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-29317","name":"3 Cam","class":"g9iii_yellow_giant","category":"star","object_type":"G9III yellow giant","mag":5.07,"mag_band":"V","abs_mag":-0.492,"abs_mag_band":"V","distance_ly":422.4824238424733,"distance_method":"parallax","ra_deg":69.97785,"dec_deg":53.079535,"epoch_ra_deg":70.508027,"epoch_dec_deg":53.132111,"epoch_moved_arcsec":0.468,"pm_ra_mas_yr":-7.38,"pm_dec_mas_yr":-15.95,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Camelopardalis","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-29317","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"04399+5305","companions":[{"measured":2015,"magnitude":12.3,"components":null,"discoverer_code":"BU 1043","separation_arcsec":1.8,"position_angle_deg":308}],"spectral_type":"G9III","color_index_bv":1.079,"luminosity_solar":137.0250597124245,"metallicity_fe_h":-0.21,"radial_velocity_km_s":-41,"spectral_type_source":"SIMBAD (1985ApJS...59...95A, quality C)","surface_gravity_log_g":2.49,"surface_temperature_k":4640,"metallicity_fe_h_source":"One spectroscopic determination, compiled from the literature (PASTEL, Soubiran+ 2016)","proper_motion_ra_mas_yr":-7.38,"proper_motion_dec_mas_yr":-15.95,"stellar_parameters_method":"Spectroscopic determinations compiled from the literature (PASTEL, Soubiran+ 2016)"},"designations":[{"catalog":"Bayer/Flamsteed","designation":"3 Cam"},{"catalog":"HD","designation":"HD 29317"},{"catalog":"HIP","designation":"HIP 21727"},{"catalog":"HR","designation":"HR 1467"}],"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."}