{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.684","julian_year":2026.684,"time":"2026-09-07T20:25:45.718Z","years_from_j2000":26.684,"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":"hd-42618-b","name":"HD 42618 b","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":79.37276376839124,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":93.0032173,"dec_deg":6.7819742,"epoch_ra_deg":93.365257,"epoch_dec_deg":6.775967,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"HD 42618","semi_major_axis_km":82877220.3678,"periapsis_km":null,"mass_kg":8.599921729619586e+25,"mass_msun":0.0000432502,"constellation":"Orion","discovered":"2016","featured":false,"url":"https://spacecatalog.org/object/hd-42618-b","radius_km":24810.809,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"HD 42618","host_v_mag":6.87,"eccentricity":0.19,"uncertainties":{"mass_kg":[1.433320288269931e+25,1.4930419669478448e+25],"distance_ly":[0.08056062529603562,0.0812129380514691],"eccentricity":[0.12,0.15],"host_mass_solar":[0.061,0.061],"host_radius_solar":[0.087,0.087],"host_temperature_k":[60,60],"semi_major_axis_km":[1645576.5776999998,1645576.5776999998],"orbital_period_days":[0.34,0.37],"argument_of_periastron_deg":[39,69]},"host_mass_solar":1.015,"stars_in_system":1,"discovery_method":"Radial Velocity","host_radius_solar":0.999,"planets_in_system":1,"discovery_facility":"Multiple Observatories","host_spectral_type":"G4 V","host_temperature_k":5727,"orbital_period_days":149.61,"transit_midpoint_bjd":2455170.6,"equilibrium_temperature_k":337,"argument_of_periastron_deg":101},"designations":[{"catalog":"Exoplanet","designation":"HD 42618 b"},{"catalog":"Host star","designation":"HD 42618"}],"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."}