{"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":"2026-09-07T02:43:37.053Z","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-168746-b","name":"HD 168746 b","class":"gas_giant","category":"exoplanet","object_type":"Gas giant","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":135.57700924567362,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":275.4573269,"dec_deg":-11.9229757,"epoch_ra_deg":275.833024,"epoch_dec_deg":-11.910549,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"HD 168746","semi_major_axis_km":10471850.949000001,"periapsis_km":null,"mass_kg":5.1249621062343615e+26,"mass_msun":0.000257742,"constellation":"Serpens","discovered":"2002","featured":false,"url":"https://spacecatalog.org/object/hd-168746-b","radius_km":70796.91,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"HD 168746","host_v_mag":7.95,"eccentricity":0.11,"uncertainties":{"mass_kg":[3.796268226840268e+25,3.796268226840268e+25],"distance_ly":[0.3245255958281597,0.32615637771674344],"eccentricity":[0.08,0.08],"host_mass_solar":[0.06,0.06],"host_radius_solar":[0.02,0.02],"host_temperature_k":[12,12],"orbital_period_days":[0.0014,0.0014],"argument_of_periastron_deg":[22,15]},"host_mass_solar":1.07,"stars_in_system":1,"discovery_method":"Radial Velocity","host_radius_solar":1.09,"planets_in_system":1,"discovery_facility":"La Silla Observatory","host_spectral_type":"G5","host_temperature_k":5570,"orbital_period_days":6.404,"periastron_epoch_bjd":2451994.7,"transit_midpoint_bjd":2454986.88,"equilibrium_temperature_k":900,"argument_of_periastron_deg":62.5},"designations":[{"catalog":"Exoplanet","designation":"HD 168746 b"},{"catalog":"Host star","designation":"HD 168746"}],"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."}