Hydranencephaly or hydrancephaly [1] is a condition in which the brain's cerebral hemispheres are absent to varying degrees and the remaining cranial cavity is filled with cerebrospinal fluid.[2]
Mission Objective. The mission objective of the Voyager Interstellar Mission (VIM) is to extend the NASA exploration of the solar system beyond the neighborhood of the outer planets to the outer limits of the Sun's sphere of influence, and possibly beyond.
Launched in 1977, Voyager was sent initially to study the outer planets, but then just kept on going. Today, the veteran Nasa mission is almost 19 billion km (12 billion miles) from home. This distance is so vast that it takes 17 hours now for a radio signal sent from Voyager to reach receivers here on Earth.