{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.815","julian_year":2026.815,"time":"2026-10-25T14:46:00.261Z","years_from_j2000":26.815,"frame":"date","applied":"Proper motion, then precession and nutation. The catalogued position is carried along the great circle the object's own published motion puts it on, at a constant velocity, from the epoch that position was measured at, 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. The motion runs from position_epoch_jyear where the upstream publishes one — a timed pulsar's position belongs to the year it was timed — and from J2000 where it does not. 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-j2257p5909","name":"PSR J2257+5909","class":"pulsar","category":"neutron_star","object_type":"Pulsar","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":10277.187461854584,"distance_method":"dispersion measure through the YMW16 electron-density model","ra_deg":344.49058476727646,"dec_deg":59.15411796097552,"epoch_ra_deg":344.766044,"epoch_dec_deg":59.298289,"epoch_moved_arcsec":0.549,"pm_ra_mas_yr":17.689062573689206,"pm_dec_mas_yr":-2.024120862030685,"position_epoch_jyear":1996.0041067761806,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Cassiopeia","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/psr-j2257p5909","source":{"id":"atnf","name":"ATNF Pulsar Catalogue (Manchester+ 2005)","url":"https://www.atnf.csiro.au/research/pulsar/psrcat","license":"No licence stated; the database is ATNF/CSIRO property under the CSIRO Legal Notice and Disclaimer","attribution":"Manchester, R. N., Hobbs, G. B., Teoh, A. & Hobbs, M. 2005, AJ 129, 1993 (2005AJ....129.1993M); https://www.atnf.csiro.au/research/pulsar/psrcat","commercial_use":"needs_permission"},"radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"spin_period_s":0.3682464543421859,"uncertainties":{"proper_motion_ra_mas_yr":[4.533152196280744,4.533152196280744],"proper_motion_dec_mas_yr":[4.52222635052195,4.52222635052195]},"position_epoch_jyear":1996.0041067761806,"spin_period_derivative":5.752952780066565e-15,"proper_motion_ra_mas_yr":17.689062573689206,"radio_flux_1400_mhz_mjy":9.2,"characteristic_age_years":1014177.104219598,"position_uncertainty_mas":33.0272152918252,"proper_motion_dec_mas_yr":-2.024120862030685,"dispersion_measure_pc_cm3":151.082,"spin_down_luminosity_erg_s":4.54815046928997e+33,"surface_magnetic_field_gauss":1472870860047.0425},"designations":[{"catalog":"ATNF","designation":"B2255+58"},{"catalog":"ATNF","designation":"J2257+5909"},{"catalog":"ATNF","designation":"PSR B2255+58"},{"catalog":"ATNF","designation":"PSR J2257+5909"}],"updated_at":"2026-10-01T09:42:28.932Z","citation":{"plain":"SpaceCatalog. PSR J2257+5909 [catalogue entry]. Data release DR1 (2026-08-21). https://spacecatalog.org/object/psr-j2257p5909","bibtex":"@misc{spacecatalog_psr-j2257p5909,\n  author       = {{SpaceCatalog}},\n  title        = {{PSR J2257+5909}},\n  howpublished = {SpaceCatalog, data release DR1 (2026-08-21)},\n  year         = {2026},\n  url          = {https://spacecatalog.org/object/psr-j2257p5909},\n  note         = {Catalogue entry, data release DR1 (2026-08-21). Values from ATNF Pulsar Catalogue (Manchester+ 2005).}\n}","url":"https://spacecatalog.org/object/psr-j2257p5909","release":"DR1","doi":null},"references":[],"attribution":"Data from SpaceCatalog.org. Each record names its upstream in `source`, with that producer's terms in `source.license`, the acknowledgement it asks for in `source.attribution`, and whether its terms allow commercial use in `source.commercial_use`; those terms govern the record, and citing SpaceCatalog does not discharge them."}