{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.847","julian_year":2026.847,"time":"2026-11-06T09:57:41.159Z","years_from_j2000":26.847,"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":"copernicus","name":"Copernicus","class":"k0iv_v_orange_subgiant","category":"star","object_type":"K0IV-V orange subgiant","mag":5.96,"mag_band":"V","abs_mag":5.503,"abs_mag_band":"V","distance_ly":40.251284730401025,"distance_method":"parallax","ra_deg":133.1492144241329,"dec_deg":28.330819,"epoch_ra_deg":133.550722,"epoch_dec_deg":28.227417,"epoch_moved_arcsec":14.473,"pm_ra_mas_yr":-485.48,"pm_dec_mas_yr":-234.4,"position_epoch_jyear":null,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Cancer","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/copernicus","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":"08526+2820","companions":[{"measured":2016,"magnitude":13.15,"components":null,"discoverer_code":"LDS6219","separation_arcsec":84.8,"position_angle_deg":128}],"radius_solar":0.974,"spectral_type":"K0IV-V","uncertainties":{"distance_ly":[0.3691426226891594,0.3760399063716903]},"color_index_bv":0.869,"luminosity_solar":0.5480245321768503,"radial_velocity_km_s":27.2,"spectral_type_source":"SIMBAD (2003AJ....126.2048G, quality C)","surface_gravity_log_g":4.451,"surface_temperature_k":5184,"proper_motion_ra_mas_yr":-485.48,"proper_motion_dec_mas_yr":-234.4,"stellar_parameters_method":"Gaia DR3 model fit (GSP-Phot, FLAME; RUWE ≤ 1.4)","bolometric_luminosity_solar":0.6176},"designations":[{"catalog":"Bayer/Flamsteed","designation":"55 Rho1 Cnc"},{"catalog":"Common name","designation":"Copernicus"},{"catalog":"Exoplanet host","designation":"55 Cnc"},{"catalog":"Gliese","designation":"Gl 324A"},{"catalog":"HD","designation":"HD 75732"},{"catalog":"HIP","designation":"HIP 43587"},{"catalog":"HR","designation":"HR 3522"}],"updated_at":"2026-11-04T19:31:31.075Z","citation":{"plain":"SpaceCatalog. Copernicus [catalogue entry]. Data release DR1 (2026-08-21). https://spacecatalog.org/object/copernicus","bibtex":"@misc{spacecatalog_copernicus,\n  author       = {{SpaceCatalog}},\n  title        = {{Copernicus}},\n  howpublished = {SpaceCatalog, data release DR1 (2026-08-21)},\n  year         = {2026},\n  url          = {https://spacecatalog.org/object/copernicus},\n  note         = {Catalogue entry, data release DR1 (2026-08-21). Values from HYG Database v4.1.}\n}","url":"https://spacecatalog.org/object/copernicus","release":"DR1","doi":null},"references":[{"bibcode":"2003AJ....126.2048G","ads_url":"https://ui.adsabs.harvard.edu/abs/2003AJ....126.2048G/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."}