{"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":"2026-09-06T20:41:56.413Z","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":"gj-876-b","name":"GJ 876 b","class":"gas_giant","category":"exoplanet","object_type":"Gas giant","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":15.248365124099871,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":343.3239737,"dec_deg":-14.2665958,"epoch_ra_deg":343.679499,"epoch_dec_deg":-14.123839,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"GJ 876","semi_major_axis_km":31163779.630611897,"periapsis_km":null,"mass_kg":4.3192121479316183e+27,"mass_msun":0.00217219,"constellation":"Aquarius","discovered":"1998","featured":false,"url":"https://spacecatalog.org/object/gj-876-b","radius_km":84828.73000000001,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"GJ 876","host_v_mag":10.16,"eccentricity":0.0324,"uncertainties":{"mass_kg":[8.54139448451523e+24,8.54139448451523e+24],"distance_ly":[0.0054468115078696155,0.0054468115078696155],"eccentricity":[0.0013,0.0013],"host_mass_solar":[0.03,0.03],"host_temperature_k":[48.39,48.39],"semi_major_axis_km":[2991.957414,2991.957414],"orbital_period_days":[0.0086,0.0086],"argument_of_periastron_deg":[3.2,3.2]},"host_mass_solar":0.32,"inclination_deg":59,"stars_in_system":1,"discovery_method":"Radial Velocity","host_radius_solar":0.3,"planets_in_system":4,"discovery_facility":"Multiple Observatories","host_spectral_type":"M2.5V","host_temperature_k":3293.74,"orbital_period_days":61.1166,"periastron_epoch_bjd":2450602.093,"transit_midpoint_bjd":2453055.984,"equilibrium_temperature_k":190.6,"argument_of_periastron_deg":50.3},"designations":[{"catalog":"Exoplanet","designation":"GJ 876 b"}],"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."}