Neptunian Satellite Data

Bulk parameters

                       Mass          Radius       Mean density    Vis. geom. albedo
                       (kg)           (km)          (kg/m3)
Naiad (NIII)                           29                               0.06
Thalassa (NIV)                         40                               0.06
Despina (NV)                           74                               0.06
Galatea (NVI)                          79                               0.06
Larissa (NVII)                      104 x 89                            0.06
Proteus (NVIII)                  218 x 208 x 201                        0.06
Triton (NI)          21.47e21        1,352.6          2,054             0.7
Neried (NII)                           170                              0.2

Orbital parameters

                         Semimajor axis          Period*  Inclination  Eccentricity
                       (e3 km)      (Rn)          (d)        (deg)
Naiad (NIII)            48.227      1.948       0.294396      4.74        0.00
Thalassa (NIV)          50.075      2.022       0.311485      0.21        0.00
Despina (NV)            52.526      2.121       0.334655      0.07        0.00
Galatea (NVI)           61.953      2.502       0.428745      0.05        0.00
Larissa (NVII)          73.548      2.970       0.554654      0.20        0.00
Proteus (NVIII)        117.647      4.751       1.122315      0.55        0.00
Triton (NI)            354.76      14.328       5.876854R   156.834
Neried (NII)         5,513.4      222.67      360.13619       7.23        0.7512