{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.686","julian_year":2026.686,"time":"2026-09-08T13:38:00.672Z","years_from_j2000":26.686,"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-109988-b","name":"HD 109988 b","class":"gas_giant","category":"exoplanet","object_type":"Gas giant","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":138.70745815899892,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":189.8154662,"dec_deg":-32.7263607,"epoch_ra_deg":190.175028,"epoch_dec_deg":-32.874089,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"HD 109988","semi_major_axis_km":1872666145.4226,"periapsis_km":null,"mass_kg":4.141897689130932e+28,"mass_msun":0.0208302,"constellation":"Hydra","discovered":"2022","featured":false,"url":"https://spacecatalog.org/object/hd-109988-b","radius_km":77175.01000000001,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"HD 109988","host_v_mag":8.9,"eccentricity":0.056,"uncertainties":{"mass_kg":[7.886707712019036e+27,4.2992522184191116e+27],"distance_ly":[0.26516513508371237,0.26646976059457933],"eccentricity":[0.034,0.036],"host_mass_solar":[0.104,0.104],"inclination_deg":[4.296,1.773],"host_radius_solar":[0.036554,0.059918],"host_temperature_k":[144.63,87.77],"semi_major_axis_km":[197319591.45329997,226939969.85189998],"orbital_period_days":[2033.89457,3942.55441],"argument_of_periastron_deg":[98.697,79.885]},"host_mass_solar":0.88,"inclination_deg":33.992,"stars_in_system":1,"discovery_method":"Radial Velocity","host_radius_solar":0.869694,"planets_in_system":1,"discovery_facility":"Multiple Observatories","host_temperature_k":5185.97,"orbital_period_days":17132.15854,"periastron_epoch_bjd":2445137.031,"equilibrium_temperature_k":65.91,"argument_of_periastron_deg":63.515},"designations":[{"catalog":"Exoplanet","designation":"HD 109988 b"},{"catalog":"Host star","designation":"HD 109988"}],"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."}