{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.682","julian_year":2026.682,"time":"2026-09-07T04:54:10.142Z","years_from_j2000":26.682,"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-28471-c","name":"HD 28471 c","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":142.35258183636125,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":66.2875166,"dec_deg":-64.0786861,"epoch_ra_deg":66.352211,"epoch_dec_deg":-64.016508,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"HD 28471","semi_major_axis_km":9723861.5955,"periapsis_km":null,"mass_kg":3.416080020376669e+25,"mass_msun":0.00001718,"constellation":"Reticulum","discovered":"2025","featured":false,"url":"https://spacecatalog.org/object/hd-28471-c","radius_km":14414.506,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"HD 28471","host_v_mag":7.89,"eccentricity":0.088,"uncertainties":{"mass_kg":[4.299960864809793e+24,3.4041356846410856e+24],"distance_ly":[0.2022169541843809,0.2028692669398144],"eccentricity":[0.054,0.058],"host_mass_solar":[0.044,0.044],"host_radius_solar":[0.057,0.057],"host_temperature_k":[101,101],"semi_major_axis_km":[149597.8707,149597.8707],"orbital_period_days":[0.0009,0.0856],"argument_of_periastron_deg":[46,222]},"host_mass_solar":0.98,"stars_in_system":1,"discovery_method":"Radial Velocity","host_radius_solar":1.08,"planets_in_system":3,"discovery_facility":"La Silla Observatory","host_spectral_type":"G5 V","host_temperature_k":5766,"orbital_period_days":6.1245,"transit_midpoint_bjd":2452945.806,"equilibrium_temperature_k":1066,"argument_of_periastron_deg":76},"designations":[{"catalog":"Exoplanet","designation":"HD 28471 c"}],"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."}