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.
After completing its primary mission with the flyby of Saturn on November 20, 1980, Voyager 1 began an extended mission to explore the regions and boundaries of the outer heliosphere.