Voyager 2 image of Thalassa.

THALASSA - MOON OF NEPTUNE

Thalassa, the daughter of Aether and Hemera, was the Greek personification of the sea (thalassa is the Greek word for sea) and said to be the creator of all sea life. Thalassa is normally regarded as the mother of Aphrodite.

Thalassa was discovered in 1989 in Voyager 2 images.

Orbit

Thalassa orbits Neptune at a distance 50,000 kilometres. It has a circular orbit but is inclined by 0.21° with respect to Neptune. It takes Thalassa 0.311 days to orbit Neptune.

The orbits of Neptune's inner moons.

Physical properties

Thalassa's diameter is about 80 kilometres. Its mass and density have not been determined.

Interior

The interior and composition of Thalassa is unknown.

Magnetic field

No magnetic field has been detected.

Atmosphere

No atmosphere has been detected, and Despina is unlikely to possess one.

Surface

Even in the best Voyager 2 image, little surface detail can be seen. Thalassa appears elongated because the image is smeared by the motion of the spacecraft.