{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.677","julian_year":2026.677,"time":"2026-09-05T09:22:17.061Z","years_from_j2000":26.677,"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":"rho-crb-b","name":"ρ CrB b","class":"gas_giant","category":"exoplanet","object_type":"Gas giant","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":56.97006065216129,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":240.2600639,"dec_deg":33.3001861,"epoch_ra_deg":240.519677,"epoch_dec_deg":33.224314,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"ρ CrB","semi_major_axis_km":33584721.97215,"periapsis_km":null,"mass_kg":2.078284557152061e+27,"mass_msun":0.0010452,"constellation":"Corona Borealis","discovered":"1997","featured":false,"url":"https://spacecatalog.org/object/rho-crb-b","radius_km":87379.97,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"ρ CrB","host_v_mag":5.40816,"eccentricity":0.046,"uncertainties":{"mass_kg":[3.2249706486073446e+23,3.2249706486073446e+23],"distance_ly":[0.07827753065201842,0.07860368702973516],"eccentricity":[0.002,0.002],"host_radius_solar":[0.0262,0.0262],"host_temperature_k":[24,24],"semi_major_axis_km":[359034.88967999996,344075.10260999994],"orbital_period_days":[0.002,0.002],"argument_of_periastron_deg":[3,3]},"host_mass_solar":1,"stars_in_system":1,"discovery_method":"Radial Velocity","host_radius_solar":1.3617,"planets_in_system":3,"discovery_facility":"Fred Lawrence Whipple Observatory","host_spectral_type":"G0","host_temperature_k":5817,"orbital_period_days":39.849,"periastron_epoch_bjd":2455499.084,"transit_midpoint_bjd":2457113.758,"equilibrium_temperature_k":614,"argument_of_periastron_deg":270.1},"designations":[{"catalog":"Exoplanet","designation":"rho CrB b"},{"catalog":"Host star","designation":"rho CrB"}],"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."}