{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.675","julian_year":2026.675,"time":"2026-09-04T11:33:59.559Z","years_from_j2000":26.675,"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":"ross-508-b","name":"Ross 508 b","class":"super_earth","category":"exoplanet","object_type":"Super-Earth","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":36.56310841118009,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":230.9613022,"dec_deg":17.4605347,"epoch_ra_deg":231.26935,"epoch_dec_deg":17.364896,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"Ross 508","semi_major_axis_km":8027421.741761999,"periapsis_km":null,"mass_kg":2.3888671471165517e+25,"mass_msun":0.000012014,"constellation":"Serpens","discovered":"2022","featured":false,"url":"https://spacecatalog.org/object/ross-508-b","radius_km":11671.923,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"Ross 508","host_v_mag":14.18,"eccentricity":0.33,"uncertainties":{"mass_kg":[3.2846923272852586e+24,3.165248969929431e+24],"distance_ly":[0.034898732415691545,0.034898732415691545],"eccentricity":[0.15,0.13],"host_mass_solar":[0.0045,0.0045],"host_radius_solar":[0.0063,0.0063],"host_temperature_k":[22,34],"semi_major_axis_km":[73302.956643,83774.80759199998],"orbital_period_days":[0.01,0.01],"argument_of_periastron_deg":[28,22]},"host_mass_solar":0.1774,"stars_in_system":1,"discovery_method":"Radial Velocity","host_radius_solar":0.2113,"planets_in_system":1,"discovery_facility":"Subaru Telescope","host_spectral_type":"M4.5 V","host_temperature_k":3071,"orbital_period_days":10.77,"periastron_epoch_bjd":2459370.24,"equilibrium_temperature_k":293.86,"argument_of_periastron_deg":-37},"designations":[{"catalog":"Exoplanet","designation":"Ross 508 b"},{"catalog":"Host star","designation":"Ross 508"}],"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."}