{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.688","julian_year":2026.688,"time":"2026-09-09T05:02:28.149Z","years_from_j2000":26.688,"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":"psr-b1257-12-b","name":"PSR B1257+12 b","class":"terrestrial_planet","category":"exoplanet","object_type":"Terrestrial planet","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":1956.9382663004606,"distance_method":"NASA Exoplanet Archive sy_dist (Konacki and Wolszczan 2003, 2003ApJ...591L.147K)","ra_deg":195.0149029,"dec_deg":12.6823534,"epoch_ra_deg":195.350955,"epoch_dec_deg":12.537361,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"PSR B1257+12","semi_major_axis_km":28423595.433,"periapsis_km":null,"mass_kg":1.1944335735582758e+23,"mass_msun":6.00698e-8,"constellation":"Virgo","discovered":"1994","featured":false,"url":"https://spacecatalog.org/object/psr-b1257-12-b","radius_km":2155.7978000000003,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"PSR B1257+12","eccentricity":0,"uncertainties":{"mass_kg":[1.1944335735582758e+22,1.1944335735582758e+22],"distance_ly":[326.1563777167434,326.1563777167434],"orbital_period_days":[0.003,0.003]},"host_mass_solar":1.4,"inclination_deg":50,"stars_in_system":1,"discovery_method":"Pulsar Timing","planets_in_system":3,"discovery_facility":"Arecibo Observatory","orbital_period_days":25.262,"periastron_epoch_bjd":2449765.6,"argument_of_periastron_deg":0},"designations":[{"catalog":"Exoplanet","designation":"PSR B1257+12 b"}],"source":{"id":"exoplanet_archive","name":"NASA Exoplanet Archive (Planetary Systems Composite Parameters)","url":"https://exoplanetarchive.ipac.caltech.edu/cgi-bin/TblView/nph-tblView?app=ExoTbls&config=PSCompPars","license":"Public domain (NASA)"},"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."}