{"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":"2026-09-08T16:20:58.496Z","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-106315-c","name":"HD 106315 c","class":"neptune_like_planet","category":"exoplanet","object_type":"Neptune-like planet","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":356.6617837245904,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":183.4724742,"dec_deg":-0.3934357,"epoch_ra_deg":183.816833,"epoch_dec_deg":-0.542879,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"HD 106315","semi_major_axis_km":22978232.939519998,"periapsis_km":null,"mass_kg":9.077695159042896e+25,"mass_msun":0.000045653,"constellation":"Virgo","discovered":"2017","featured":false,"url":"https://spacecatalog.org/object/hd-106315-c","radius_km":27744.735,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"HD 106315","host_v_mag":8.951,"eccentricity":0.22,"uncertainties":{"mass_kg":[2.2097021110828105e+25,2.2097021110828105e+25],"radius_km":[1466.9630000000002,1466.9630000000002],"distance_ly":[2.2211249322510227,2.2537405700226967],"eccentricity":[0.15,0.15],"host_mass_solar":[0.036,0.036],"inclination_deg":[0.25,0.7],"host_radius_solar":[0.058,0.058],"host_temperature_k":[48,48],"semi_major_axis_km":[254316.38018999997,254316.38018999997],"orbital_period_days":[0.00046,0.00046],"argument_of_periastron_deg":[35,88]},"host_mass_solar":1.091,"inclination_deg":88.61,"stars_in_system":1,"discovery_method":"Transit","host_radius_solar":1.296,"planets_in_system":2,"discovery_facility":"K2","host_spectral_type":"F5 V","host_temperature_k":6327,"orbital_period_days":21.05704,"transit_midpoint_bjd":2457569.0173,"equilibrium_temperature_k":886,"argument_of_periastron_deg":96},"designations":[{"catalog":"Exoplanet","designation":"HD 106315 c"}],"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."}