{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.675","julian_year":2026.675,"time":"2026-09-04T11:20:10.276Z","years_from_j2000":26.675,"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-7023","name":"Iris Nebula","class":"nebula","category":"nebula","object_type":"Nebula","mag":7.2,"mag_band":"B","abs_mag":null,"abs_mag_band":null,"distance_ly":null,"distance_method":null,"ra_deg":315.39841666666666,"dec_deg":68.16955555555556,"epoch_ra_deg":315.475843,"epoch_dec_deg":68.274473,"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":"Cepheus","discovered":"1794","featured":false,"url":"https://spacecatalog.org/object/ngc-7023","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"b_mag":7.2,"wikidata_id":"Q649379","also_known_as":["NAME IRIS Nebula"],"discovered_by":"William Herschel","ngc_type_code":"Neb","major_axis_arcmin":10,"minor_axis_arcmin":8,"wikipedia_article":"Iris Nebula"},"designations":[{"catalog":"Caldwell","designation":"C 4"},{"catalog":"Common name","designation":"Iris Nebula"},{"catalog":"IAU cluster","designation":"C 2059+679"},{"catalog":"IRAS","designation":"IRAS 20599+6755"},{"catalog":"IRAS","designation":"IRAS 21009+6758"},{"catalog":"IRAS","designation":"IRAS F20599+6755"},{"catalog":"LBN","designation":"LBN 487"},{"catalog":"Lynds","designation":"LBN 104.08+14.21"},{"catalog":"NGC","designation":"NGC 7023"}],"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."}