{"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":"2026-08-27T17:42:14.264Z","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-106983","name":"ζ Cru","class":"b2_3v_blue_white_main_sequence_star","category":"star","object_type":"B2/3V blue-white main-sequence star","mag":4.06,"mag_band":"V","abs_mag":-1.14,"abs_mag_band":"V","distance_ly":357.62753275900974,"distance_method":"parallax","ra_deg":184.60947,"dec_deg":-64.003071,"epoch_ra_deg":184.973796,"epoch_dec_deg":-64.152263,"epoch_moved_arcsec":0.927,"pm_ra_mas_yr":-33.19,"pm_dec_mas_yr":-10.38,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Crux","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-106983","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"12184-6400","companions":[{"measured":2015,"magnitude":12.49,"components":null,"discoverer_code":"HJ 4512","separation_arcsec":33.6,"position_angle_deg":345}],"spectral_type":"B2/3V","color_index_bv":-0.168,"luminosity_solar":248.8857318282393,"radial_velocity_km_s":16,"spectral_type_source":"SIMBAD (1975MSS...C01....0H, quality D)","proper_motion_ra_mas_yr":-33.19,"proper_motion_dec_mas_yr":-10.38},"designations":[{"catalog":"Bayer/Flamsteed","designation":"Zeta Cru"},{"catalog":"HD","designation":"HD 106983"},{"catalog":"HIP","designation":"HIP 60009"},{"catalog":"HR","designation":"HR 4679"}],"source":{"id":"hyg","name":"HYG Database v4.1","url":"https://github.com/astronexus/HYG-Database","license":"CC-BY-SA-4.0"},"updated_at":"2026-08-27T16:03:54.983Z","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."}