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]
JPL built and operates the twin Voyager spacecraft. The Voyagers Interstellar Mission is a part of NASA's Heliophysics System Observatory, sponsored by the Heliophysics Division of NASA's Science Mission Directorate in Washington.
On August 25, 2012, data from Voyager 1 indicated that it had become the first human-made object to enter interstellar space, traveling further than anyone, or anything, in history. As of 2013, Voyager 1 was moving with a velocity of 17 kilometers per second (11 mi/s) relative to the Sun.