{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.814","julian_year":2026.814,"time":"2026-10-25T09:08:43.868Z","years_from_j2000":26.814,"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-j1856m3754","name":"PSR J1856-3754","class":"x_ray_isolated_neutron_star","category":"neutron_star","object_type":"X-ray isolated neutron star","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":397.75168014237005,"distance_method":"pulsar parallax (timing or VLBI)","ra_deg":284.14754166666665,"dec_deg":-37.90994444444444,"epoch_ra_deg":284.609371,"epoch_dec_deg":-37.875169,"epoch_moved_arcsec":7.716,"pm_ra_mas_yr":325.9,"pm_dec_mas_yr":-59.22,"position_epoch_jyear":2003.5195071868584,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Corona Australis","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/psr-j1856m3754","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":{"associations":"XRS:RX_J1856.5-3754,OPT:[kkvh11]","spin_period_s":7.055202873998977,"uncertainties":{"distance_ly":[39.33807825583881,49.03787837371692],"proper_motion_ra_mas_yr":[0.30000000000000004,0.30000000000000004],"proper_motion_dec_mas_yr":[0.18,0.18]},"position_epoch_jyear":2003.5195071868584,"spin_period_derivative":2.976598078078349e-14,"proper_motion_ra_mas_yr":325.9,"characteristic_age_years":3755392.605127934,"position_uncertainty_mas":1904.078793124239,"proper_motion_dec_mas_yr":-59.22,"spin_down_luminosity_erg_s":3.346196296411301e+30,"surface_magnetic_field_gauss":14664417954614.82},"designations":[{"catalog":"ATNF","designation":"J1856-3754"},{"catalog":"ATNF","designation":"PSR J1856-3754"}],"updated_at":"2026-10-01T09:42:28.932Z","citation":{"plain":"SpaceCatalog. PSR J1856-3754 [catalogue entry]. Data release DR1 (2026-08-21). https://spacecatalog.org/object/psr-j1856m3754","bibtex":"@misc{spacecatalog_psr-j1856m3754,\n  author       = {{SpaceCatalog}},\n  title        = {{PSR J1856-3754}},\n  howpublished = {SpaceCatalog, data release DR1 (2026-08-21)},\n  year         = {2026},\n  url          = {https://spacecatalog.org/object/psr-j1856m3754},\n  note         = {Catalogue entry, data release DR1 (2026-08-21). Values from ATNF Pulsar Catalogue (Manchester+ 2005).}\n}","url":"https://spacecatalog.org/object/psr-j1856m3754","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."}