{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.673","julian_year":2026.673,"time":"2026-09-03T21:24:47.234Z","years_from_j2000":26.673,"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-604","name":"NGC 604","class":"h_ii_region","category":"nebula","object_type":"H II region","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":null,"distance_method":null,"ra_deg":23.638291666666667,"dec_deg":30.78488888888889,"epoch_ra_deg":24.017186,"epoch_dec_deg":30.922571,"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":"Triangulum","discovered":"1784","featured":false,"url":"https://spacecatalog.org/object/ngc-604","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wikidata_id":"Q506389","discovered_by":"William Herschel","ngc_type_code":"HII","major_axis_arcmin":1.93,"minor_axis_arcmin":1.2,"wikipedia_article":"NGC 604"},"designations":[{"catalog":"IRAS","designation":"IRAS 01317+3031"},{"catalog":"NGC","designation":"NGC 604"}],"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."}