SAO

Sao may refer to:

SAO or S.A.O. may stand for:

Sao civilisation

The Sao civilization flourished in Middle Africa from ca. the sixth century BC to as late as the sixteenth century AD. The Sao lived by the Chari River south of Lake Chad in territory that later became part of Cameroon and Chad. They are the earliest people to have left clear traces of their presence in the territory of modern Cameroon. Sometime around the 16th century, conversion to Islam changed the cultural identity of the former Sao. Today, several ethnic groups of northern Cameroon and southern Chad but particularly the Sara, Kotoko claim descent from the civilization of the Sao.

Origins and decline

The Sao civilization may have begun as early as the sixth century BC, and by the end of the first millennium BC, their presence was well established south of Lake Chad and near the Chari River. The city states of the Sao reached their apex sometime between the ninth and fifteenth centuries AD.

The Sao's demise may have come about due to conquest, Islamization, or both. Traditional tales say that the Sao west of Lake Chad fell to "Yemenites" from the east. These invaders made several unsuccessful attempts to conquer the Sao before finally succeeding by resorting to trickery. If true, the newcomers may have been Arab Bedouin or Sayfuwa raiders coming from the east who moved into the region in the fourteenth century . Although some scholars estimate that the Sao civilization south of Lake Chad lasted until the fourteenth or fifteenth century, the majority opinion is that it ceased to exist as a separate culture sometime in the 16th century subsequently to the expansion of the Bornu Empire. The Kotoko are the inheritors of the former city states of the Sao.

Sao (moon)

Sao (/ˈseɪ.oʊ/ SAY-oh; Greek: Σαώ) is a prograde irregular satellite of Neptune. It was discovered by Matthew J. Holman et al. on August 14, 2002.

Sao orbits Neptune at a distance of about 22.4 million km and is about 44 kilometers in diameter (assuming an albedo of 0.04).

Sao follows an exceptionally inclined and moderately eccentric orbit illustrated on the diagram in relation to other irregular satellites of Neptune. The satellites above the horizontal axis are prograde, the satellites beneath it are retrograde. The yellow segments extend from the pericentre to the apocentre, showing the eccentricity.

The satellite is in so-called Kozai resonance, i.e. its inclination and eccentricity are coupled (the inclination of the orbit decreases while eccentricity increases and vice versa).

Sao, or Neptune XI, like many of the outer satellites of Neptune, is named after one of the Nereids; Sao was associated with sailing and is referred to as "The rescuer" or "Safety". Before the announcement of its name on February 3, 2007 (IAUC 8802), Sao was known provisionally as S/2002 N 2.