{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.686","julian_year":2026.686,"time":"2026-09-08T17:09:38.683Z","years_from_j2000":26.686,"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":"ugc-3660","name":"UGC 3660","class":"barred_spiral_galaxy_sba","category":"galaxy","object_type":"Barred spiral galaxy SBa","mag":13.578,"mag_band":"B","abs_mag":-20.347758278899388,"abs_mag_band":"B","distance_ly":198873781.15614784,"distance_method":"luminosity distance from a spectroscopic redshift (GLADE+), flat ΛCDM with H0 = 70 km/s/Mpc","ra_deg":106.644974,"dec_deg":63.848877,"epoch_ra_deg":107.281811,"epoch_dec_deg":63.807445,"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":"Camelopardalis","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/ugc-3660","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"b_mag":13.578,"h_mag":10.18,"j_mag":10.856,"k_mag":9.872,"redshift":0.01422,"hubble_type":"SBa","redshift_cmb":0.0140866243023449,"uncertainties":{"distance_ly":[11154292.052350331,11156175.308398519],"stellar_mass_solar":[7473419674.725009,7473419674.725009]},"major_axis_arcmin":2.0142,"minor_axis_arcmin":1.09633,"morphology_source":"SIMBAD (2003A&A...412...45P, quality E)","position_angle_deg":108,"stellar_mass_solar":15881016808.790644},"designations":[{"catalog":"2MASX","designation":"2MASX 07063479+6350559"},{"catalog":"PGC","designation":"PGC 20158"},{"catalog":"WISExSCOS","designation":"WISExSCOS J070634.83+635055.9"}],"source":{"id":"glade_plus","name":"GLADE+ (Galaxy List for the Advanced Detector Era)","url":"https://cdsarc.cds.unistra.fr/viz-bin/cat/VII/291","license":"VizieR terms; cite Dalya+ 2022 (2022MNRAS.514.1403D)"},"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."}