{"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":"2026-09-03T18:03:23.528Z","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-6366","name":"NGC 6366","class":"globular_cluster","category":"cluster","object_type":"Globular cluster","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":11741.629597802763,"distance_method":"Globular-cluster distance scale (Harris 2010)","ra_deg":261.93470833333333,"dec_deg":-5.076638888888889,"epoch_ra_deg":262.291926,"epoch_dec_deg":-5.099424,"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":"Ophiuchus","discovered":"1860","featured":false,"url":"https://spacecatalog.org/object/ngc-6366","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"redshift":-0.000402,"wikidata_id":"Q1145326","discovered_by":"Friedrich August Theodor Winnecke","ngc_type_code":"GCl","major_axis_arcmin":13.8,"wikipedia_article":"NGC 6366","distance_reference":"NGC 6366","radial_velocity_km_s":-121},"designations":[{"catalog":"IAU cluster","designation":"C 1725-050"},{"catalog":"MWSC","designation":"MWSC 2601"},{"catalog":"NGC","designation":"NGC 6366"}],"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."}