The Voyager 2 spacecraft is a 1,592 lb. space probe launched by NASA on August
20, 1977 to study the outer Solar System and eventually interstellar space. Operating
for 33 years, 11 months and 31 days as of today (20 August 2011), the spacecraft receives routine commands and transmits data back to the Deep Space Network.

Each Voyager space probe carries a gold-plated audio-visual disc (shown below) in
the event that either spacecraft is ever found by intelligent life-forms from other
planetary systems. The discs carry photos of the Earth and its life forms, a range
of scientific information, spoken greetings from the people (e.g. the Secretary-
General of the United Nations and the President of the United States, and the
children of the Planet Earth) and a medley, "Sounds of Earth", that includes the
sounds of whales, a baby crying, waves breaking on a shore, and a variety
of music.

Voyager’s 12 inch gold plated disc

Diagram of the main components of the Voyager spacecraft. (click to enlarge)