{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.680","julian_year":2026.68,"time":"2026-09-06T06:11:42.373Z","years_from_j2000":26.68,"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":"ngc4054-ned01","name":"NGC4054 NED01","class":"spiral_galaxy_sbc","category":"galaxy","object_type":"Spiral galaxy Sbc","mag":15.45,"mag_band":"B","abs_mag":null,"abs_mag_band":null,"distance_ly":496141528.5732098,"distance_method":"redshift (CMB frame), flat ΛCDM with H0 = 70 km/s/Mpc","ra_deg":180.80191666666667,"dec_deg":57.89344444444444,"epoch_ra_deg":181.145711,"epoch_dec_deg":57.743875,"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":"Ursa Major","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/ngc4054-ned01","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"b_mag":15.45,"h_mag":12.76,"j_mag":13.13,"k_mag":12.67,"redshift":0.03409,"hubble_type":"Sbc","redshift_cmb":0.03461549962177379,"ngc_type_code":"G","uncertainties":{"distance_ly":[24601101.735498417,24601101.735498417]},"major_axis_arcmin":0.65,"minor_axis_arcmin":0.43,"position_angle_deg":91,"surface_brightness":23.12,"radial_velocity_km_s":10046},"designations":[{"catalog":"2MASX","designation":"2MASX J12031243+5753363"},{"catalog":"MCG","designation":"MCG +10-17-131 NED01"},{"catalog":"OpenNGC","designation":"NGC4054 NED01"},{"catalog":"SDSS","designation":"SDSS J120312.46+575336.4"}],"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."}