Thalassa

E118792

Thalassa is a small, inner irregularly shaped moon of Neptune that orbits close to the planet within its ring system.

All labels observed (1)

Label Occurrences
Thalassa canonical 3

How this entity was disambiguated

Statements (47)

Predicate Object
instanceOf irregularly shaped moon
moon of Neptune
natural satellite
adjectiveForm Thalassan
albedo low
belongsToGroup inner moons of Neptune
celestialBodyType inner moon
diameter_km ~80
discoveredBy Richard J. Terrile
Voyager imaging team
surface form: Voyager 2 imaging team
discoveredBySpacecraft Voyager 2
discoveryContext Voyager 2
surface form: Voyager 2 Neptune flyby
discoveryDate 1989-09-18
discoveryMethod spacecraft imaging
equilibriumState non-spherical
escapeVelocity_m_per_s ~40
exploredBy Voyager 2
gravitationalBinding bound to Neptune
IAUNameStatus approved
locatedIn Neptune system
surface form: Neptunian system
mass_estimate very low (exact value uncertain)
meanDensity_g_per_cm3 ~1.2 (approximate)
meanRadius_km ~40
namedAfter Greek mythological figure
Thalassa
surface form: Thalassa (sea nymph in Greek mythology)
namedBy International Astronomical Union
neighboringMoon Despina
Naiad
orbitalDirection prograde
orbitalEccentricity ~0.0002
orbitalInclination_deg ~0.21
orbitalPeriod_days ~0.311
orbits Neptune
orbitsWithin Neptune ring system
parentPlanet Neptune
provisionalDesignation S/1989 N5
relativePosition orbits inside Despina
orbits outside Naiad
ringAssociation orbits near the inner Neptunian rings
rotation synchronous with Neptune
rotationState tidally locked to Neptune
semiMajorAxis_km ~50,074
shape irregular
surfaceComposition likely water ice with dark material
surfaceFeatures no prominent large craters resolved
system Neptune system
surface form: Neptune satellite system
visibilityFromEarth telescopic only

How these facts were elicited

Referenced by (3)

Full triples — surface form annotated when it differs from this entity's canonical label.

Neptune moon Thalassa
Galatea neighboringMoons Thalassa