{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.678","julian_year":2026.678,"time":"2026-09-05T11:38:20.528Z","years_from_j2000":26.678,"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-21152-b","name":"HIP 21152 b","class":"gas_giant","category":"exoplanet","object_type":"Gas giant","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":141.57567734463996,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":68.0205209,"dec_deg":5.4100745,"epoch_ra_deg":68.377811,"epoch_dec_deg":5.467733,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"HIP 21152","semi_major_axis_km":2543163801.8999996,"periapsis_km":null,"mass_kg":4.555499039416129e+28,"mass_msun":0.0229103,"constellation":"Taurus","discovered":"2022","featured":false,"url":"https://spacecatalog.org/object/hip-21152-b","radius_km":76537.20000000001,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"HIP 21152","host_v_mag":6.37009,"eccentricity":0.36,"uncertainties":{"mass_kg":[7.592498399026883e+27,1.1388747598540323e+28],"distance_ly":[0.4249817601649167,0.4275910111866506],"eccentricity":[0.25,0.37],"host_mass_solar":[0.05,0.05],"inclination_deg":[2.1,3.9],"host_radius_solar":[0.055903,0.06669],"host_temperature_k":[125,125],"semi_major_axis_km":[598391482.8,747989353.5],"orbital_period_days":[5800,11000],"argument_of_periastron_deg":[130,160]},"host_mass_solar":1.4,"inclination_deg":95.3,"stars_in_system":2,"discovery_method":"Imaging","host_radius_solar":1.59186,"planets_in_system":1,"discovery_facility":"Multiple Observatories","host_spectral_type":"F5 V","host_temperature_k":6655,"orbital_period_days":22000,"periastron_epoch_bjd":2463360,"transit_midpoint_bjd":2449000,"equilibrium_temperature_k":1300,"argument_of_periastron_deg":160},"designations":[{"catalog":"Exoplanet","designation":"HIP 21152 b"},{"catalog":"Host star","designation":"HIP 21152"}],"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."}