Complex sentence: The Sigma Octantis (south pole star) is small, but all the other stars turn around it; the only position in the sky of south hemisphere represents the stability of the Federal District in the Brazilian Union.
Split into simpler sentences: The Sigma Octantis (south pole star) is small, but all the other stars turn around it. Its unique position in the sky of south hemisphere represents the stability of the Federal District in the Brazilian union.