The Southern Cross

Purpose

The Southern Cross is used as a navigational aid at night in the southern hemisphere due to its high visibility.
Navigators would often draw a long imaginary line down the body of the cross to find the southern sky pole, and calculate from there.

Geography

The Southern Cross is a constellation that can only be seen in the southern hemisphere. Thus, only people in the African region, southern half of the New World, or Australia would be likely to see it.
When seen in the night sky, one can imagine that the four stars are connected by lines to form a cross.
Because the four large stars are so bright, they can be seen clearly when out at sea, assuming favorable weather.

Fauna & Flora

Being in space, there is nothing known to live there. Though some imaginative sailors came up with yarns that the divine beings live up in parts of the constellation.

Natural Resources

Nobody has been able to fly up there and explore it, even if they wanted to prove the sailors' yarns as fakes.

History

Known since the classical days of ancient Greece, the cross was considered part of a different constellation. It used to be visible in northern skies as well, until the stars moved away.
Only when the Tang Mariners went to seek the New World did they rediscover the Southern Cross, though they called it the Kite. This was not widely publicized as the Mariners preferred the northern half of the New World.
After this, when the Europeans started seeking out Africa, they independently rediscovered the Southern Cross as well.
Indigenous locals of the southern hemisphere had different interpretations of the cross, generally viewing at as some sort of animal pattern in the sky.

Alternative Name(s)

Crux
South Cross-shaped constellation (Tangguo)
Kite (Ancient Tang Mariner)

Type

Star System