Voyager 2 was launched by NASA on August 20, 1977 to study the outer Solar System and eventually interstellar space. It was actually launched before Voyager 1, but Voyager 1 moved faster and eventually passed it. Voyager 2 has been operating for 37 years, 7 months and 6 days as of 26 March 2015, and the Deep Space Network is still receiving its data transmissions. At a distance of 106.65 AU from the Sun as of December 11, 2014, it is one of the most distant human-made objects.

Voyager 2 is part of the Voyager program with its identical sister craft Voyager 1, and is in extended mission, tasked with locating and studying the boundaries of the Solar System, including the Kuiper belt, the heliosphere, and

interstellar space.

Conceived in the 1960s, a proposal to study the outer planets prompted NASA to begin work on a mission in the early 1970s. The development of the interplanetary probes coincided with an alignment of the planets, making possible a mission to the outer Solar System by taking advantage of the then-new technique of gravity assist.

It was determined that utilizing gravity assists would enable a single probe to visit the four gas giants (Jupiter, Saturn, Uranus, and Neptune) while requiring a minimal amount of propellant and a shorter transit duration between planets.

Voyager: Intergalactic Message In A Bottle

Carrying messages to ET from Earth on a gold record

Once its planetary mission was over, Voyager 2 was described as working on an interstellar mission, which NASA is using to find out what the Solar System is like beyond the heliosphere. Voyager 2 is currently transmitting scientific data at about 160 bits per second. Information about continuing telemetry exchanges with Voyager 2 is available from Voyager Weekly Reports.

On November 29, 2006, a telemetered command to Voyager 2 was incorrectly decoded by its on-board computer as a command to turn on the electrical heaters of the spacecraft’s magnetometer. These heaters remained turned on until December 4, 2006, It had not been possible to fully diagnose and correct for the damage caused to Voyager 2’s magnetometer, although efforts to do so were proceeding.

On August 30, 2007, Voyager 2 passed the termination shock and then entered into the heliosheath, approximately 1 billion miles (1.6

billion km) closer to the Sun than Voyager 1 did.

Voyager 2 is expected to enter interstellar space within a few years of 2016, and its plasma spectrometer should provide the first direct measurements of the density and temperature of the interstellar plasma.

Voyager 2 is not headed toward any particular star, although in roughly 40,000 years it should pass 1.7 light-years from the star Ross 248. And if undisturbed for 296,000 years, it should pass by the star Sirius at a distance of 4.3 light-years. Voyager 2 is expected to keep transmitting weak radio messages until at least 2025, over 48 years after it was launched.

On September 12, 2013, NASA announced that Voyager 1 left the Solar System and entered interstellar space.

“Someday humans will leave our cocoon in the solar system to explore beyond our home sys-

tem, Voyager will have led the way.”

Voyager 2 launch, August 20, 1977 (courtsey of NASA)

The contents of the record were selected for NASA by a committee chaired by Carl Sagan of Cornell University. Sagan and his associates assembled 116 images and a variety of natural sounds, such as those made by surf, wind, thunder and animals (including the songs of birds and whales). They also added musical selections from different cultures and eras, spoken greetings in 55 ancient and modern languages, and printed messages from US president Jimmy Carter and U.N. Secretary-General Kurt Waldheim.

The collection of images includes many photographs and diagrams both in black and white and color. The first images are of scientific interest, showing mathematical and physical quantities, the Solar System and its planets, DNA, and human anatomy and reproduction. Care was taken to include not only pictures of humanity, but also some of animals, insects, plants and landscapes. Images of humanity

depict a broad range of cultures and activities.

Voyager’s Golden Records (Courtsey of NASA)

The Voyager Golden Records are phonograph records which were included aboard both Voyager spacecraft, which were launched in 1977. They contain sounds and images selected

to portray the diversity of life and culture on Earth, and are intended for any intelligent extraterrestrial life form, or for future humans, who may find them.

Technicians installing the record onto Voyager 1 (courtesy of NASA)

In the upper left-hand corner is an easily recognized drawing of the phonograph record and the stylus carried with it. The stylus is in the correct position to play the record from the beginning. The drawing indicates that the record should be played from the outside in. Below this drawing is a side view of the record and stylus, with a binary number giving the time to play one side of the record – about an hour.

The record is constructed of gold-plated copper. The record’s cover is aluminum and electroplated upon it is an ultra-pure sample of the isotope uranium-238. Uranium-238 has a half-life of 4.468 billion years. It is possible (e.g. via mass-spectrometry) that a civilization that encounters the record will be able to use

the ratio of remaining uranium to daughter elements to determine the age of the record. The records also had the inscription “To the makers of music – all worlds, all times” hand-etched on its surface. The inscription was located in the “takeout grooves”, an area of the record between the label and playable surface.

So what will become of Voyagers 1 & 2? Once their on board fuel goes empty, they will drift silently on their current path, forever going onwards, until man in the future finds the small probes, or another civilization finds it drifting

lifeless and is perplexed by where it came from.

Saturn, taken from Voyager 2 (Courtesy of NASA)

Refrences:“Voyager - The Interstellar Mission.” Voyager - The Interstellar Mission. Web. 30 Mar. 2015. <http://voyager.jpl.nasa.gov/index.html>.“Voyager Golden Record.” Wikipedia. Wikimedia Foundation. Web. 30 Mar. 2015. <http://en.wikipedia.org/wiki/Voy-

ager_Golden_Record>.

“Billions of years from now our sun, then a distended red giant star, will have reduced Earth to a charred cinder. But the Voyager record will still be largely intact, in some other remote region of the Milky Way galaxy, preserving a murmur of an ancient civilization that once flourished — perhaps before moving on to greater deeds and other worlds — on the distant planet Earth.”

- Carl Sagan

Picture of the solar system, taken by Voyager 1. Its the only picture taken with all the planets in it.

(courtsey of NASA)