The Cerebellum(the back of the brain) coordinates voluntary muscle movements and maintains posture, balance and equilibrium.
Integumentary system I believe
It is about 4.22 light-years<span> from Earth and is the closest star other than the sun. Alpha Centauri A and B orbit a common center of gravity every 80 years. The average distance between them is </span>about 11 astronomical units<span> (AU) — about the same distance as the sun is to Uranus.</span>