35-year-old Voyager 2 is NASA's longest mission ever

[CBS]   The iconic Voyager 2 spacecraft celebrated its 35th birthday Monday (Aug. 20) in a milestone for NASA's longest-running mission ever.  Voyager 2 launched in 1977 just 16 days before its twin, Voyager 1. The probes were tasked chiefly with studying Saturn, Jupiter and the gas giants' moons, but have continued on through the solar system and are now about to cross into interstellar space. Voyager 1 is due to cross first, becoming the first manmade object to travel beyond our solar system, and Voyager 2 is not far behind.