{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.684","julian_year":2026.684,"time":"2026-09-07T17:31:27.188Z","years_from_j2000":26.684,"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-687-c","name":"GJ 687 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":14.838125632207753,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":264.1041731,"dec_deg":68.3336741,"epoch_ra_deg":264.074673,"epoch_dec_deg":68.315979,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"GJ 687","semi_major_axis_km":174281519.3655,"periapsis_km":null,"mass_kg":9.555468588466207e+25,"mass_msun":0.0000480558,"constellation":"Draco","discovered":"2020","featured":false,"url":"https://spacecatalog.org/object/gj-687-c","radius_km":26405.334,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"GJ 687","host_v_mag":9.15,"eccentricity":0.4,"uncertainties":{"mass_kg":[2.4485888257944653e+25,2.4485888257944653e+25],"distance_ly":[0.002217863368473855,0.002217863368473855],"eccentricity":[0.22,0.22],"host_mass_solar":[0.02,0.02],"host_radius_solar":[0.007,0.007],"host_temperature_k":[28,28],"semi_major_axis_km":[3440751.0260999994,3440751.0260999994],"orbital_period_days":[12.198,12.198],"argument_of_periastron_deg":[63,63]},"host_mass_solar":0.4,"stars_in_system":1,"discovery_method":"Radial Velocity","host_radius_solar":0.4183,"planets_in_system":2,"discovery_facility":"Multiple Observatories","host_spectral_type":"M3.0V","host_temperature_k":3413,"orbital_period_days":727.562,"periastron_epoch_bjd":2450304.1,"equilibrium_temperature_k":98.62,"argument_of_periastron_deg":176},"designations":[{"catalog":"Exoplanet","designation":"GJ 687 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."}