{"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":"2026-09-08T10:40:15.858Z","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-3649","name":"UGC 3649","class":"spiral_galaxy_sa","category":"galaxy","object_type":"Spiral galaxy Sa","mag":13.492,"mag_band":"B","abs_mag":-20.74851414285597,"abs_mag_band":"B","distance_ly":229894564.82193533,"distance_method":"luminosity distance from a spectroscopic redshift (GLADE+), flat ΛCDM with H0 = 70 km/s/Mpc","ra_deg":106.005737,"dec_deg":29.243406,"epoch_ra_deg":106.430748,"epoch_dec_deg":29.203845,"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":"Gemini","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/ugc-3649","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"b_mag":13.492,"h_mag":10.266,"j_mag":10.999,"k_mag":9.947,"redshift":0.017,"hubble_type":"Sa","redshift_cmb":0.0162575244444444,"uncertainties":{"distance_ly":[15024645.61431215,15027036.295515323],"stellar_mass_solar":[9341647120.990158,9341647120.990158]},"major_axis_arcmin":0.9,"minor_axis_arcmin":0.468,"morphology_source":"SIMBAD (2003A&A...412...45P, quality E)","position_angle_deg":65,"stellar_mass_solar":28024941362.970474},"designations":[{"catalog":"2MASX","designation":"2MASX 07040137+2914362"},{"catalog":"PGC","designation":"PGC 20087"},{"catalog":"WISExSCOS","designation":"WISExSCOS J070401.37+291436.6"}],"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."}