Depending on where you are on earth you will see the northern or the southern hemisphere.
This southern hemisphere was described in 1500 by physician-astronomer Mestre João Faras in his letter of May 1, 1500, to King Manuel I of Portugal from the newly discovered land of Brazil.
The smallest of all constellations (Crux); was than described as "Las Guardias" (the Guardians).
|'las guardias' (now Southern Cross)|
The constellation might be the smallest, it's one of the most important on the southern hemisphere, as it helps us to find the South.
|southern hemisphere - determinating the South|
|northern hemisphere - determinating the North|
The Crux (Southern Cross) is the most important constellation.
If you continue the virtual line between the α-star and the γ-star, and you take the bisector between the α-star and the β-star of the Centauri constellation, the crossing of those 2 lines will indicate more or less the south. α-centauri is the nearest start to Earth, after the Sun.
For the north, you have to prolonge the last part of the 'Urs Major' (Big Dipper / Great Bear) 4 and a half times, you can find the north.
The 'southern cross' can be found in many flags of countries of the southern hemisphere:
|southern cross on flags|
And of course, for the purpose of this topic; also on the flag of Brazil...
|can you find the southern cross on the Brazilian flag?|