Voyager 2 image of Larissa.

LARISSA - MOON OF NEPTUNE

Larissa was a daughter of Pelasgus, the King of Argos. Although Larissa was imaged by Voyager 2 in 1989, it was actually discovered by Harold Reitsma, who found it by observing the occultation of stars. A body passing in front of a star will cause it to blink.

Orbit

Larissa orbits Neptune at a distance of 73,600 kilometres. Larissa's orbit is inclined 0.2 o to Neptune's equatorial plane, and is very nearly a perfect circle with a 0.0014 eccentricity. It takes Larissa just over half a day to make one orbit around Neptune.

The orbits of Neptune's inner moons.

Physical properties

It has an average diameter of 193 kilometres, but is irregular like Proteus. On one axis it measures 208 kilometres and on the other, 178 kilometres.

Interior

The interior and composition of Larissa is unknown.

Magnetic field

No magnetic field has been detected.

Atmosphere

No atmosphere has been detected.

Surface

Though the Voyager image is very vague, the surface of Larissa appears heavily cratered.