Nearly 30 years ago, the Voyager 1 space probe was leaving the Solar System and was about to become the first object to cross the outermost edge of the ‘heliosphere’ and enter the space between star systems. NASA was delighted with what the probe had achieved, including ‘flybys’ of Jupiter, Saturn and Saturn’s large moon, Titan.
Dr Carl Sagan, the American astronomer, cosmologist and science communicator – best known for the award-winning 1980 TV series Cosmos: A Personal Voyage – had proposed the idea of Voyager 1 turning its camera around and taking one last picture of Earth before crossing the ‘heliopause’ and entering the ‘interstellar medium’. He accepted that such a picture would have very little scientific merit, but that it could hold considerable meaning as a perspective on our place in the universe. Although many in NASA had technical concerns about such a re-tasking, they agreed to Sagan’s request.
On 14th February 1990, at a record six billion kilometres from Earth, NASA instructed Voyager 1’s Imaging Science Subsystem to rotate and take a series of images of the planets in the Solar System – a series of images that became known as the ‘Family Portrait series’. Amongst these was the image of Earth (Earth is the pale blue-coloured speck about half way down the brown band two-thirds of the way across the image – here).
During a public lecture at Cornell University in 1994, Carl Sagan showed the image of what he called ‘The Pale Blue Dot’ and shared his reflections on its deeper meaning:
“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.”
Incidentally, it was Carl Sagan who argued the now-accepted hypothesis that the high surface temperatures on Venus can be attributed to, and calculated using, the ‘greenhouse effect’.
As we begin 2018 and look forward to the 70th Anniversary of the formation of IFRF, lets re-double our determination to “preserve and cherish the pale blue dot” in our sphere of activity – industrial combustion and flame research.
Season’s greetings to all our Members!