{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.687","julian_year":2026.687,"time":"2026-09-08T19:06:01.490Z","years_from_j2000":26.687,"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":"lhs-1903-d","name":"LHS 1903 d","class":"neptune_like_planet","category":"exoplanet","object_type":"Neptune-like planet","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":116.4107558655269,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":107.865826,"dec_deg":48.3279327,"epoch_ra_deg":108.370554,"epoch_dec_deg":48.283613,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"LHS 1903","semi_major_axis_km":12871400.795028,"periapsis_km":null,"mass_kg":3.559412049203662e+25,"mass_msun":0.0000179008,"constellation":"Lynx","discovered":"2026","featured":false,"url":"https://spacecatalog.org/object/lhs-1903-d","radius_km":15945.25,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"LHS 1903","host_v_mag":12.23,"eccentricity":0.112,"uncertainties":{"mass_kg":[6.748549690604257e+24,6.867993047960086e+24],"radius_km":[491.1137,497.4918],"distance_ly":[0.27168826263804724,0.27168826263804724],"eccentricity":[0.044,0.055],"host_mass_solar":[0.03,0.039],"host_radius_solar":[0.014,0.014],"host_temperature_k":[70,70],"semi_major_axis_km":[278252.03950199997,266284.20984599995],"orbital_period_days":[0.000028,0.000032],"argument_of_periastron_deg":[19,29]},"host_mass_solar":0.538,"stars_in_system":1,"discovery_method":"Transit","host_radius_solar":0.539,"planets_in_system":4,"discovery_facility":"Transiting Exoplanet Survey Satellite (TESS)","host_spectral_type":"M","host_temperature_k":3664,"orbital_period_days":12.566287,"transit_midpoint_bjd":2458844.3901,"equilibrium_temperature_k":442,"argument_of_periastron_deg":233},"designations":[{"catalog":"Exoplanet","designation":"LHS 1903 d"},{"catalog":"Host star","designation":"LHS 1903"}],"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."}