{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.669","julian_year":2026.669,"time":"2026-09-02T05:02:15.446Z","years_from_j2000":26.669,"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-6901","name":"NGC 6901","class":"barred_spiral_galaxy_sbab","category":"galaxy","object_type":"Barred spiral galaxy SBab","mag":14.83,"mag_band":"B","abs_mag":null,"abs_mag_band":null,"distance_ly":213061524.2243435,"distance_method":"redshift (CMB frame), flat ΛCDM with H0 = 70 km/s/Mpc","ra_deg":305.589625,"dec_deg":6.429861111111111,"epoch_ra_deg":305.919712,"epoch_dec_deg":6.515325,"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":"Aquila","discovered":"1863","featured":false,"url":"https://spacecatalog.org/object/ngc-6901","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"b_mag":14.83,"h_mag":10.82,"j_mag":11.55,"k_mag":10.48,"redshift":0.016011,"hubble_type":"SBab","wikidata_id":"Q1148393","redshift_cmb":0.015080371084132516,"discovered_by":"Albert Marth","ngc_type_code":"G","uncertainties":{"distance_ly":[16539704.592965197,16539704.592965197]},"major_axis_arcmin":1.25,"minor_axis_arcmin":0.49,"position_angle_deg":62,"surface_brightness":23.37,"radial_velocity_km_s":4762},"designations":[{"catalog":"2MASX","designation":"2MASX J20222151+0625475"},{"catalog":"IC","designation":"IC 5000"},{"catalog":"IRAS","designation":"IRAS 20199+0616"},{"catalog":"LEDA","designation":"LEDA 64552"},{"catalog":"MCG","designation":"MCG +01-52-002"},{"catalog":"NGC","designation":"NGC 6901"},{"catalog":"PGC","designation":"PGC 64552"},{"catalog":"SDSS","designation":"SDSS J202221.52+062547.5"},{"catalog":"UGC","designation":"UGC 11542"}],"source":{"id":"openngc","name":"OpenNGC","url":"https://github.com/mattiaverga/OpenNGC","license":"CC-BY-SA-4.0"},"updated_at":"2026-09-01T22:58:55.274Z","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."}