The Voyager space mission is arguably one of mankind's greatest achievements of the 20th century, and one which nearly never got off the ground.
In 1964 Gary Flandro of the Jet Propulsion Laboratory discovered that Jupiter, Saturn, Uranus, and Neptune would align in such a way that a probe could use a gravity assist to visit them all. And so the Grand Tour program was born at NASA in 1966.
There was one major problem; this special planetary alignment would only happen once every 175 years and the next one would happen in 1977, giving NASA only ten years to complete the build and launch phase. The challenge was daunting as nothing like this had ever been done before, despite this engineers and programmers worked around the clock and managed to get two probes ready just months before the launch window closed.
Would Voyager 2 and 1 work? Would the spacecraft’s programming work the instruments correctly and plot the correct course through the solar system with the aid of scientists? Well, it did and it is the first and only time we have visited all the planets in our solar system in one run.
As we watch the Voyager: To the Final Frontier documentary film, we see how this historic mission which has been ongoing for more than 40 years happened.