Naiad (moon)

Naiad
Naiad as seen by Voyager 2 (elongation is due to smearing)
Discovery
Discovered byVoyager Imaging Team
Discovery dateSeptember 1989
Designations
Designation
Neptune III
Pronunciation/ˈneɪəd/ or /ˈnaɪæd/,[1][2]
/ˈneɪəd/ or /ˈnaɪəd/[3]
Named after
pl. Ναϊάδες Nāïades
AdjectivesNaiadian /-ˈædiən/[4]
Orbital characteristics[5][6]
Epoch 18 August 1989
48 224.41  km
Eccentricity0.0047 ± 0.0018
0.2943958 ± 0.0000002 d
Inclination
  • 4.75 ± 0.03° (to Neptune equator)
  • 4.75° (to local Laplace plane)
Satellite ofNeptune
Physical characteristics
Dimensions(96±8) × (60±16) × (52±8) km[7]
33±3 km[7]
Mass~1.2×1017 kg (calculated)
Mean density
0.80±0.48 g/cm3[8]
synchronous
zero
Albedo0.072[7][9]
Temperature~51 K mean (estimate)
23.91[9]

Naiad /ˈneɪəd/, (also known as Neptune III and previously designated as S/1989 N 6) named after the naiads of Greek legend,[10] is the innermost satellite of Neptune and the nearest to the center of any gas giant with moons with a distance of 48,224 km from the planet's center. Its orbital period is less than a Neptunian day, resulting in tidal dissipation that will cause its orbit to decay. Eventually it will either crash into Neptune's atmosphere or break up to become a new ring.[11]

  1. ^ Noah Webster (1884) A Practical Dictionary of the English Language
  2. ^ "naiad". Oxford English Dictionary (Online ed.). Oxford University Press. (Subscription or participating institution membership required.)
  3. ^ "naiad". Merriam-Webster.com Dictionary. Merriam-Webster.
  4. ^ Morris (1904) British violin-makers
  5. ^ Cite error: The named reference Jacobson2004 was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference Showalter2019 was invoked but never defined (see the help page).
  7. ^ a b c Cite error: The named reference Karkoschka2003 was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference Brozovic2019 was invoked but never defined (see the help page).
  9. ^ a b Cite error: The named reference jplssd was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference USGS-Gazetteer was invoked but never defined (see the help page).
  11. ^ "Naiad". NASA Science Solar System Exploration. NASA.