{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.808","julian_year":2026.808,"time":"2026-10-23T07:17:34.080Z","years_from_j2000":26.808,"frame":"date","applied":"Proper motion, then precession and nutation. The catalogued position is carried along the great circle the object's own published motion puts it on, at a constant velocity, from the epoch that position was measured at, 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. The motion runs from position_epoch_jyear where the upstream publishes one — a timed pulsar's position belongs to the year it was timed — and from J2000 where it does not. 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-122980","name":"χ Cen","class":"b2v_blue_white_main_sequence_star","category":"star","object_type":"B2V blue-white main-sequence star","mag":4.36,"mag_band":"V","abs_mag":-1.612,"abs_mag_band":"V","distance_ly":510.416792525929,"distance_method":"parallax","ra_deg":211.51155,"dec_deg":-41.179633,"epoch_ra_deg":211.924378,"epoch_dec_deg":-41.308668,"epoch_moved_arcsec":0.875,"pm_ra_mas_yr":-24.42,"pm_dec_mas_yr":-21.63,"position_epoch_jyear":null,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Centaurus","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-122980","source":{"id":"hyg","name":"HYG Database v4.1","url":"https://github.com/astronexus/HYG-Database","license":"CC-BY-SA-4.0","attribution":"HYG Database v4.1, Astronexus (github.com/astronexus/HYG-Database). Fields derived from it stay under CC BY-SA 4.0.","commercial_use":"allowed"},"radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"14060-4111","companions":[{"measured":2016,"magnitude":8.49,"components":"AB","discoverer_code":"WFC 145","separation_arcsec":85.2,"position_angle_deg":78},{"measured":2016,"magnitude":11,"components":"AC","discoverer_code":"DAM 775","separation_arcsec":101.8,"position_angle_deg":195}],"mass_solar":6.545,"radius_solar":5.041,"spectral_type":"B2V","uncertainties":{"metallicity_fe_h":[0.146,0.146]},"color_index_bv":-0.198,"luminosity_solar":384.4147117595778,"metallicity_fe_h":-0.1,"variability_type":"CST:","variable_mag_max":4.353,"variable_mag_min":4.373,"variability_class":"Not variable (GCVS)","radial_velocity_km_s":12,"spectral_type_source":"SIMBAD (2012AJ....144..130B, quality D)","variable_designation":"Chi Cen","surface_gravity_log_g":3.785,"surface_temperature_k":18871,"metallicity_fe_h_source":"Median of 3 spectroscopic determinations in 4 papers, compiled from the literature (PASTEL, Soubiran+ 2016); the error bar is the scatter between them","proper_motion_ra_mas_yr":-24.42,"proper_motion_dec_mas_yr":-21.63,"stellar_parameters_method":"Gaia DR3 model fit (GSP-Phot, FLAME; RUWE ≤ 1.4) — low confidence: above 7,500 K GSP-Phot's temperature and extinction are degenerate","bolometric_luminosity_solar":2006.0005},"designations":[{"catalog":"Bayer/Flamsteed","designation":"Chi Cen"},{"catalog":"HD","designation":"HD 122980"},{"catalog":"HIP","designation":"HIP 68862"},{"catalog":"HR","designation":"HR 5285"}],"updated_at":"2026-10-01T09:42:28.932Z","citation":{"plain":"SpaceCatalog. χ Cen [catalogue entry]. Data release DR1 (2026-08-21). https://spacecatalog.org/object/hd-122980","bibtex":"@misc{spacecatalog_hd-122980,\n  author       = {{SpaceCatalog}},\n  title        = {{χ Cen}},\n  howpublished = {SpaceCatalog, data release DR1 (2026-08-21)},\n  year         = {2026},\n  url          = {https://spacecatalog.org/object/hd-122980},\n  note         = {Catalogue entry, data release DR1 (2026-08-21). Values from HYG Database v4.1.}\n}","url":"https://spacecatalog.org/object/hd-122980","release":"DR1","doi":null},"references":[{"bibcode":"2012AJ....144..130B","ads_url":"https://ui.adsabs.harvard.edu/abs/2012AJ....144..130B/abstract","quantity":"properties.spectral_type_source"}],"attribution":"Data from SpaceCatalog.org. Each record names its upstream in `source`, with that producer's terms in `source.license`, the acknowledgement it asks for in `source.attribution`, and whether its terms allow commercial use in `source.commercial_use`; those terms govern the record, and citing SpaceCatalog does not discharge them."}