In 1960, a young engineer Gary Flandro was working for the Jet Propulsion Laboratory and stumbled upon an alignment of Jupiter, Saturn, Uranus and Neptune. He realised he could take advantage of their gravitational fields by sending unmanned probes which could investigate planets of the outer solar system in a “Planetary Grand Tour”.
In 1977 NASA launched two (unmanned) probes Voyager 1 and 2 to study the outer solar system and beyond.
Both of the voyager probes carry a gold plated audio-visual disc which is designed to capture the human race and earth as it was when the probes were launched. They will remain long after the earth is gone, potentially to be found by intelligent life, elsewhere in the universe. On it are photos, diagrams and sounds chosen by a committee, which was lead by astrophysicist, Carl Sagan. Among other things, they included diagrams of DNA and the solar system, photos and sounds of nature, music such as Beethoven and messages spoken in 56 different languages. After everything and everyone we’ve ever seen on this planet is gone, as are our descendants and any evidence of what we might accomplish during our lives is gone, voyagers one and two will still be there- drifting in space, the only remains of our entire civilization.
|Gold plated audio-visual disc|
The Voyager probes reached Jupiter in 1979, discovering the frozen seas of Europa and the sulphur volcanoes of Io before travelling on to Saturn, with its beautiful rings and unknown moons. Voyager two went on to the outer planets, but Voyager One moved up and away from the plane of the planets, moving towards interstellar space.
On Wednesday 14th February 1990, Voyager One turned around and looked back at the entire solar system.
On one photograph is a pale blue dot, less than a pixel in size, the earth. Carl Sagan, who had helped to design the probes, reflected:
“From this distant vantage point, the Earth might not seem of any particular interest. But for us, it's different. Consider again that dot. That's here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every "superstar," every "supreme leader," every saint and sinner in the history of our species lived there – on a mote of dust suspended in a sunbeam.The Earth is a very small stage in a vast cosmic arena. Think of the rivers of blood spilled by all those generals and emperors so that in glory and triumph they could become the momentary masters of a fraction of a dot. Think of the endless cruelties visited by the inhabitants of one corner of this pixel on the scarcely distinguishable inhabitants of some other corner. How frequent their misunderstandings, how eager they are to kill one another, how fervent their hatreds. Our posturings, our imagined self-importance, the delusion that we have some privileged position in the universe, are challenged by this point of pale light. Our planet is a lonely speck in the great enveloping cosmic dark. In our obscurity – in all this vastness – there is no hint that help will come from elsewhere to save us from ourselves.
The Earth is the only world known, so far, to harbor life. There is nowhere else, at least in the near future, to which our species could migrate. Visit, yes. Settle, not yet. Like it or not, for the moment, the Earth is where we make our stand. It has been said that astronomy is a humbling and character-building experience. There is perhaps no better demonstration of the folly of human conceits than this distant image of our tiny world. To me, it underscores our responsibility to deal more kindly with one another and to preserve and cherish the pale blue dot, the only home we've ever known.”
See also: Blue Marble: 40 Years On
See also: Blue Marble: 40 Years On