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The Voyager 1  spacecraft is a 733-kilogram robotic space probe of the outer solar system September 5, 1977, and currently operational. It visited Jupiter and Saturn and was the first probe to provide detailed images of the moons of these planets.

The US space agency’s (Nasa) venerable Voyager mission is celebrating its 30th anniversary.

Its two probes were launched within weeks of each other in 1977 to make a detailed study of the outer planets.

The probes were then sent on trajectories that will eventually take them out of the Solar System and into interstellar space.

Three decades on, they continue to return data from distances more than three times farther away than Pluto.

Currently, Voyager 1 is farthest away. Launched on 5 September 1977, it is about 15.5 billion km (9.7 billion miles) from the Sun.

To communicate with distant spacecraft, NASA’s Deep Space Network uses antenna with a diameter of up to 70 meters (230 feet). That is almost as big as a football field.

One of NASA’s most venerable spacecrafts celebrated three decades of flight Wednesday - thanks in large part to the efforts of the Savannah River Site.

Launched September 5, 1977 from Cape Canaveral, Fl., the Voyager 1 spacecraft is currently an estimated 9.7 billion miles from the sun, further than any other human-made object.

Arguably the only thing even more impressive than the vast distance traveled by the craft is the fact that it continues to relay information collected by its onboard instruments back to NASA.

“The Voyager mission is a legend in the annals of space exploration,” said Alan Stern, an associate administrator at NASA. “It opened our eyes to the scientific richness of the outer solar system, and it has pioneered the deepest exploration of the sun’s domain ever conducted.”

The craft, along with sister ship Voyager 2, are responsible for some of the most detailed information and images of the outer giant planets in our solar system - Jupiter, Saturn, Uranus and Neptune - ever gathered.

The instruments responsible for collecting that data owe their longevity to an onboard nuclear battery - called a radioisotope thermoelectric generator, or RTG - that is fueled by plutonium 238, a material that was produced and purified at SRS.

“All of that information, all of those pictures you see in a textbook, all that detail, those are all things that we wouldn’t know” if it were not for the nuclear battery, said Thomas Robinson, who worked on the plutonium production for the Cassini-Huygens mission, one of more than 20 NASA crafts that have employed the RTGs onboard since 1961.

The RTG itself is relatively rather basic, say SRS experts. The battery relies on the plutonium’s decay to produce heat, which in turn is then converted into electricity to power the onboard instruments.

“Over the years the principal has remained the same, but the efficiency has improved,” said Charles Goergen, who also worked on the Cassini project at SRS.

NASA was forced to turn to nuclear science in order to ensure that their crafts would have a suitable amount of energy to operate in the depths of outer space. Solar panels were not an option because they fail to capture enough of the sun’s rays to be effective once the crafts start to leave Earth behind.

“That’s why we use (the plutonium),” said Rick Burns. “It provides a steady, continuous source of power that is reliable over a long period of time.”

The craft’s five instruments run on only around 300 watts, the amount of power needed to light up a bright light bulb, and NASA is capable of turning off one or more of the instruments if the RTG’s output were to wane.

Adding to the already large scale of the project is the golden record that each of the two Voyagers carry. The records act as a time capsule complete with greetings, images and sounds from Earth - as well as directions on how to find the planet if it is ever recovered by something or someone.

While many at SRS are familiar with the concept of their work being used on a grand stage, they say working with NASA was especially satisfying.

“There is a great deal of pride involved” for those at SRS that worked on the space projects, said Goergen. “We know that we played a role in the whole thing, it really means something.”