{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.681","julian_year":2026.681,"time":"2026-09-06T16:55:41.249Z","years_from_j2000":26.681,"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":"wasp-47-d","name":"WASP-47 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":863.5968569183931,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":331.203092,"dec_deg":-12.019067,"epoch_ra_deg":331.562901,"epoch_dec_deg":-11.888873,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"WASP-47","semi_major_axis_km":12715819.0095,"periapsis_km":null,"mass_kg":9.256860195076638e+25,"mass_msun":0.0000465541,"constellation":"Aquarius","discovered":"2015","featured":false,"url":"https://spacecatalog.org/object/wasp-47-d","radius_km":23280.065000000002,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"WASP-47","host_v_mag":11.936,"eccentricity":0.001,"uncertainties":{"mass_kg":[5.374951081012241e+24,4.1805175074539655e+24],"radius_km":[191.34300000000002,191.34300000000002],"distance_ly":[15.38153477312162,15.942523742794418],"eccentricity":[0.0007,0.0008],"host_mass_solar":[0.047,0.047],"inclination_deg":[0.1,0.1],"host_radius_solar":[0.009,0.009],"host_temperature_k":[60,60],"semi_major_axis_km":[403914.25088999997,403914.25088999997],"orbital_period_days":[0.000013,0.000013],"argument_of_periastron_deg":[3,18]},"host_mass_solar":1.058,"inclination_deg":89.23,"stars_in_system":1,"discovery_method":"Transit","host_radius_solar":1.156,"planets_in_system":4,"discovery_facility":"K2","host_spectral_type":"G9","host_temperature_k":5565,"orbital_period_days":9.030501,"transit_midpoint_bjd":2457024.430107,"equilibrium_temperature_k":885,"argument_of_periastron_deg":83},"designations":[{"catalog":"Exoplanet","designation":"WASP-47 d"}],"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."}