{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.653","julian_year":2026.653,"time":"2026-08-27T16:19:32.294Z","years_from_j2000":26.653,"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":"sgr-a","name":"Sagittarius A*","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":26673,"distance_method":null,"ra_deg":266.41684,"dec_deg":-29.00781,"epoch_ra_deg":266.843448,"epoch_dec_deg":-29.018901,"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":8.251900963396911e+36,"mass_msun":4150000,"constellation":"Sagittarius","discovered":"1974","featured":true,"url":"https://spacecatalog.org/object/sgr-a","radius_km":null,"radius_kind":null,"data_quality":null,"description":"The supermassive black hole at the center of the Milky Way. For decades it was known only by the frantic orbits of nearby stars; in 2022 the Event Horizon Telescope resolved its glowing ring directly. Everything in our galaxy — including you — orbits this point.","properties":{"accretion":"hot-flow","mass_solar":4150000,"disc_inclination_deg":30},"designations":[{"catalog":"Common name","designation":"Sagittarius A*"},{"catalog":"Common name","designation":"Sgr A*"}],"source":{"id":"curated","name":"SpaceCatalog curated data","url":"https://spacecatalog.org/releases","license":"CC-BY-4.0"},"updated_at":"2026-08-27T16:03:54.983Z","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."}