A simulated view of Thalassa orbiting Neptune.

Thalassa (tha-las'-a, Greek Θάλασσα) is the second moon of Neptune. Thalassa was named after a daughter of Aether and Hemera from Greek mythology. "Thalassa" is also the Greek word for "sea". Image File history File links Download high resolution version (1152x845, 35 KB)A simulated view of Thalassa orbiting Neptunein proper position. ... Image File history File links Download high resolution version (1152x845, 35 KB)A simulated view of Thalassa orbiting Neptunein proper position. ... A computer simulation or a computer model is a computer program which attempts to simulate an abstract model of a particular system. ... Atmospheric characteristics Surface pressure ≫100 MPa Hydrogen - H2 80% ±3. ... Moons of solar system scaled to Earths Moon The common noun moon (not capitalized) is used to mean any natural satellite of the other planets. ... Atmospheric characteristics Surface pressure ≫100 MPa Hydrogen - H2 80% ±3. ... The aether (also spelled ether) is a substance concept, historically used in science and philosophy. ... In Greek mythology, Hemera was a primordial goddess, born of Erebus. ... Greek mythology comprises the collected narratives of Greek gods, goddesses, heroes, and heroines, originally created and spread within an oral-poetic tradition. ... Sunset at sea Look up Sea on Wiktionary, the free dictionary Look up maritime on Wiktionary, the free dictionary. ...

Thalassa was discovered sometime before mid-September, 1989 from the images taken by the Voyager 2 probe. It was given the temporary designation S/1989 N 5. It is also designated Neptune IV. 1989 (MCMLXXXIX) is a common year starting on Sunday of the Gregorian calendar. ... The Voyager 2 spacecraft was launched in 1977. ... A space probe is an unmanned space mission in which a spacecraft leaves Earths orbit. ...

The discovery was announced (IAUC 4867) on September 29, 1989, but the text only talks of "25 frames taken over 11 days", giving a discovery date of sometime before September 18. September 29 is the 272nd day of the year (273rd in leap years). ... 1989 (MCMLXXXIX) is a common year starting on Sunday of the Gregorian calendar. ... September 18 is the 261st day of the year (262nd in leap years). ...

It is irregularly shaped and shows no sign of any geological modification .Since the Thalassian orbit is below Neptune's orbit, it is slowly breaking up due to tidal forces and will one day break up into a planetary ring or crash into Neptune's atmosphere.Soon,the overlapping debris enter into Despina's orbit. Comet Shoemaker-Levy 9 after breaking up under the influence of Jupiters tidal forces. ... A planetary ring is a ring of dust and other small particles orbiting around a planet in a flat disc-shaped region. ... Despina is a figure in Greek mythology. ...

• Orbital radius: 50,075 km
• Diameter: 108×100×52 km
• Mass: 3.7×10¹⁷ kg
• Estimated Density: 1.3 g/cm³
• Orbital period: 0.311 d (7 h 30 min)
• Orbital inclination: 0.200° (to Neptune's equator), 0.209° (to the local Laplace plane), 28.40° (to the ecliptic)

The Laplace plane is defined as the mean plane occupied by the orbit of a satellite during a precession cycle. ... The plane of the ecliptic is well seen in this picture from the 1994 lunar prospecting Clementine spacecraft. ...