{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.678","julian_year":2026.678,"time":"2026-09-05T14:47:30.734Z","years_from_j2000":26.678,"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-105211","name":"η Cru","class":"f2v_yellow_white_main_sequence_star","category":"star","object_type":"F2V yellow-white main-sequence star","mag":4.14,"mag_band":"V","abs_mag":2.662,"abs_mag_band":"V","distance_ly":64.43219241794266,"distance_method":"parallax","ra_deg":181.720305,"dec_deg":-64.61373,"epoch_ra_deg":182.07068,"epoch_dec_deg":-64.763539,"epoch_moved_arcsec":1.355,"pm_ra_mas_yr":34.27,"pm_dec_mas_yr":-37.49,"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-105211","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"12069-6437","companions":[{"measured":2015,"magnitude":12.16,"components":"AC","discoverer_code":"HJ 4501","separation_arcsec":35.2,"position_angle_deg":195},{"measured":2015,"magnitude":11.8,"components":"AB","discoverer_code":"HJ 4501","separation_arcsec":48.8,"position_angle_deg":300}],"spectral_type":"F2V","color_index_bv":0.353,"luminosity_solar":7.502396279074636,"radial_velocity_km_s":9,"spectral_type_source":"SIMBAD (2006AJ....132..161G, quality C)","surface_temperature_k":6939,"proper_motion_ra_mas_yr":34.27,"proper_motion_dec_mas_yr":-37.49,"stellar_parameters_method":"Spectroscopic determinations compiled from the literature (PASTEL, Soubiran+ 2016)"},"designations":[{"catalog":"Bayer/Flamsteed","designation":"Eta Cru"},{"catalog":"Gliese","designation":"Gl 455.2"},{"catalog":"HD","designation":"HD 105211"},{"catalog":"HIP","designation":"HIP 59072"},{"catalog":"HR","designation":"HR 4616"}],"source":{"id":"hyg","name":"HYG Database v4.1","url":"https://github.com/astronexus/HYG-Database","license":"CC-BY-SA-4.0"},"updated_at":"2026-09-02T19:50:56.720Z","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."}