{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.672","julian_year":2026.672,"time":"2026-09-03T09:39:14.212Z","years_from_j2000":26.672,"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":"ngc-6543","name":"Cat's Eye Nebula","class":"planetary_nebula","category":"nebula","object_type":"Planetary nebula","mag":9.01,"mag_band":"V","abs_mag":null,"abs_mag_band":null,"distance_ly":5293.518010342746,"distance_method":"Statistical distance scale for planetary nebulae (Stanghellini+ 2008)","ra_deg":269.639125,"dec_deg":66.63319444444444,"epoch_ra_deg":269.63724,"epoch_dec_deg":66.629954,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Draco","discovered":"1786","featured":true,"url":"https://spacecatalog.org/object/ngc-6543","radius_km":null,"radius_kind":null,"data_quality":null,"description":"The first planetary nebula whose spectrum was ever examined, in 1864 — the observation that proved nebulae could be glowing gas rather than unresolved stars.","properties":{"b_mag":9.79,"h_mag":9.08,"j_mag":8.95,"k_mag":8.34,"v_mag":9.01,"redshift":-0.000219,"wikidata_id":"Q15829","also_known_as":["'''Cat's Eye Nebula'''"],"discovered_by":"William Herschel","ngc_type_code":"PN","major_axis_arcmin":0.9,"wikipedia_article":"Cat's Eye Nebula","distance_reference":"NGC 6543","radial_velocity_km_s":-66},"designations":[{"catalog":"2MASX","designation":"2MASX J17583335+6637591"},{"catalog":"Caldwell","designation":"C 6"},{"catalog":"Common name","designation":"Cat's Eye Nebula"},{"catalog":"HD","designation":"HD 164963"},{"catalog":"IRAS","designation":"IRAS 17584+6638"},{"catalog":"IRAS","designation":"IRAS 17584+6638A"},{"catalog":"IRAS","designation":"IRAS F17585+6638"},{"catalog":"NGC","designation":"NGC 6543"},{"catalog":"PN","designation":"PN G096.4+29.9"}],"source":{"id":"openngc","name":"OpenNGC","url":"https://github.com/mattiaverga/OpenNGC","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."}