{"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":"2026-09-02T12:40:19.930Z","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":"ton-618","name":"TON 618","class":"supermassive_black_hole","category":"black_hole","object_type":"Supermassive black hole","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":10800000000,"distance_method":null,"ra_deg":187.10402,"dec_deg":31.47712,"epoch_ra_deg":187.437879,"epoch_dec_deg":31.328556,"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":1.3123505146607136e+41,"mass_msun":65999999999.99999,"constellation":"Canes Venatici","discovered":"1957","featured":true,"url":"https://spacecatalog.org/object/ton-618","radius_km":null,"radius_kind":null,"data_quality":null,"description":"One of the most massive black holes known — sixty-six billion Suns. It powers a hyperluminous quasar whose light left it when the universe was less than a third of its current age.","properties":{"accretion":"quasar","mass_solar":66000000000},"designations":[{"catalog":"Common name","designation":"TON 618"}],"source":{"id":"curated","name":"SpaceCatalog curated data","url":"https://spacecatalog.org/releases","license":"CC-BY-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."}