{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.670","julian_year":2026.67,"time":"2026-09-02T14:43:26.395Z","years_from_j2000":26.67,"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":"hip-48655","name":"HIP 48655","class":"sdo_blue_subdwarf","category":"star","object_type":"sdO blue subdwarf","mag":12.8,"mag_band":"V","abs_mag":null,"abs_mag_band":null,"distance_ly":null,"distance_method":null,"ra_deg":148.83121500000001,"dec_deg":51.616395,"epoch_ra_deg":149.273564,"epoch_dec_deg":51.488668,"epoch_moved_arcsec":3.375,"pm_ra_mas_yr":-81.57,"pm_dec_mas_yr":-96.74,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Ursa Major","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hip-48655","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"spectral_type":"sdO","color_index_bv":-0.33,"variable_mag_max":12.675,"variable_mag_min":12.915,"radial_velocity_km_s":0,"spectral_type_source":"SIMBAD (1969ApJ...158..281G, quality D)","surface_gravity_log_g":4.4,"surface_temperature_k":36308,"proper_motion_ra_mas_yr":-81.57,"proper_motion_dec_mas_yr":-96.74,"stellar_parameters_method":"Spectroscopic determinations compiled from the literature (PASTEL, Soubiran+ 2016)"},"designations":[{"catalog":"HIP","designation":"HIP 48655"}],"source":{"id":"hyg","name":"HYG Database v4.1","url":"https://github.com/astronexus/HYG-Database","license":"CC-BY-SA-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."}