Saturday 16 February 2019

The Pioneer Plaque

The Pioneer Plaque

An understanding of scientific concepts has allowed us as a species to begin to think beyond our world and to imagine what it might be like to meet an extra-terrestrial being. When we as a species decide that we want to communicate with Aliens, what do we do? We send them a drawing, and in this case it is a drawing of which we know quite a lot about the decisions made as to why the images on it are what they are. 

Pioneer 10


In 1972, an attempt to contact extra-terrestrial life began with the launch of the Pioneer 10 spacecraft, a vehicle designed to attain enough velocity to escape the solar system and therefore the possibility of reaching an extra-terrestrial civilisation. The idea of including a specially crafted message that was designed to be read by any extra-terrestrials it might bump into, was a late addition and was overseen by Dr. Carl Sagan, Professor Frank Drake  and artist Linda Salzman.

The problem these three had to solve was whether they could come up with any universally understood concepts that could be communicable to intelligent extra-terrestrial life. The first principle that was decided upon when this question was being debated was that the only similarity between Earth bound humans and any extra-terrestrial civilisation would be that we belong to the same universe. Because it is science and mathematics that we use to understand that universe, it was further reasoned that this would be the same for any other species. Hence the Pioneer Plaque was initiated, which would operate as a symbolic message to any 
extra-terrestrials the Pioneer 10 might encounter. This plaque was designed to be attached to the exterior of Pioneer 10 and had its visual language developed by directly linking the drawing on the plaque to clear, fundamental scientific concepts.
The first issue decided upon was to set out a standard for the measurement of distance and time, a standard that could then be used throughout the plaque to ensure consistency. In order to do this it was decided that hydrogen, the most abundant element in the cosmos, would be the element around which a communication system would be evolved. Therefore it was decided to draw a symbolic representation of two hydrogen atoms at the top left of the plaque, each in a different energy state.


Image of hydrogen atoms as inscribed on the Pioneer plaque

The text immediately below is how the image is described in a scientific journal, the hyper-links were also in the description, so I have left them in because they give an idea of how complex this idea is. 

'The image above is of a schematic representation of the hyperfine transition of hydrogen, the most abundant element in the universe. The spin-flip transition of a hydrogen atom’s electron has a frequency of about 1420.405 MHz, which corresponds to a period of 0.704 ns. Light at this frequency has a vacuum wavelength of 21.106 cm (which is also the distance the light travels in that time period). Below the symbol, the small vertical line—representing the binary digit 1—specifies a unit of length (21 cm) as well as a unit of time (0.7 ns). Both units are also used as measurements in the other symbols'.

I presume the scientists behind this thinking thought that the creatures that would meet Pioneer would also be scientists. Not just that but that as scientists they would also think like earth scientists. 


Fundamental concepts such as the hydrogen atom can however be described in several ways and the concept of a schematic representation is itself a very complex one, one that would have first of all been introduced to people like Sagan in school science classrooms. Below are a few other representations of Hydrogen and its electron. There are several problems with the decision to use the symbol chosen. For instance ionised hydrogen, i.e. a hydrogen atom stripped of its electron and existing as a free proton, is pretty common in the interstellar medium, and solar wind. So the format of one proton surrounded by one electron doesn't always describe the state of hydrogen. It has also been established that the electron  moves in a wave pattern around an elliptical orbit. This orbit is often referred to as a cloud, because the electron operates in three dimensional space and moves so fast it is in effect occupying a cloud of possible positions. The idea of a static symbol like a dot or spot, would be hard for anyone outside of a small sub-group to understand. 








Words can be put together in different ways to say the same thing. For instance we can rewrite the paragraph above like this: 


'When atoms of hydrogen change from one energy state to another—a process called the hyperfine transition—electromagnetic radiation is released. It is this wave that harbours the standard of measure used throughout the illustrations on the plaque. The wavelength (approximately 21 centimeters) serves as a spatial measurement, and the period (approximately .7 nanoseconds) serves as a measurement of time. The final detail of this schematic is a small tick between the atoms of hydrogen, assigning these values of distance and time to the binary number 1'.

As you can see from both the written and drawn illustrations above, there are several ways to visualise or verbalise the idea of a hydrogen atom, in particular how do you visualise an idea that is in many places at once and is always in movement? Does a fast moving electron appear to be more like a pixelated cloud, or does it look more like a series of linked wave forms, or would an external observer be more likely to be aware of the presence of antimatter and would expect this to be represented too?

Bees draw by flying dancing patterns through the air, what would a life form that had a similar evolutionary history to that of a bee make of this plaque? 

The most prominent figures on the plaque are those of two adult humans: a man and woman. The man bends his arm and displays an open palm. At the time it was believed that this was an internationally agreed greeting on the Earth, but it would be meaningless to an extraterrestrial civilisation and even on some parts of the Earth a naked man with his arm raised could be seen as a threat. The drawing could just as well have been done upside down and from the back for all the sense someone who wasn't trained in the conventions of reading a drawing would make of it. When photographs were first shown to Amazonian Indians they apparently couldn't recognise what they were, so even it would appear indexical systems such as photography are culturally learnt. We are so immersed in a photographically centred culture that we have forgotten, or never noticed that we had to learn what photographs represented. The woman hangs her arms by her sides and stands with her weight shifted rearward apparently to dispel any misunderstandings regarding a fixed body and limb position; it was drawn this way to show that we are mobile and flexible. There was little thought going into the relative positions between the representation of the man and the woman. The man is active, raising his arm in salute, the woman passive, her body less confrontational. Another totally accepted cultural norm of the 1970s is in place. As well of course of the stylised haircuts that might as well be hats or strange growths 
and the fact that both figures have no facial or body hair, factors that speak so much about cultural norms of the time. The man's haircut and woman's hair style single them out as young mature white western caucasians, their hair, facial features and body types set out according to a particular norm or measure, (no one is too old, disabled, fat or too thin) that other people, races and cultures were at the time measured against. 
Beside the illustrations of the humans is the binary number 8, inscribed between two ticks, indicating the height the woman. The extra-terrestrial being is supposed to conclude that the woman is 8 units tall, the unit being the wavelength (21 centimeters) described by the hyperfine transition key; thus, the woman is 8 times 21 centimeters, or about 5.5 feet tall.
At the heart of the plaque is an exploding star shape of lines and dashes. In the centre of this star format is meant to be our home star, the sun; the radial spokes signify the relative distances and directions to pulsars, (rapidly rotating neutron stars that emit electromagnetic radiation at regular intervals). Accompanying each line is the period of the respective pulsar, once again, in binary. Not only does this map communicate position, but time as well. The rate of electromagnetic bursts from pulsars changes over time; thus, the period of the pulsars denoted on the plaque serves as a timestamp. It was presumed that a civilisation that has developed radio astronomy would have the capability to comprehend the nature of pulsars. Which they may well have, but far more complex a problem for them to solve would be the interpretation of this plaque. As a further confirmation of where the Earth is, our solar system’s planets are depicted along the bottom edge of the plaque with their respective distances to the sun in binary. A line with an arrowhead leaves from the third circle from the large circle on the left and a small drawing of what looks like a falling sailing boat is next to it. This represents Pioneer 10 leaving the Earth, the third planet from the sun. The problem being that the relative sizes of the spacecraft, sun and planets and distances between them can't be represented in such a small drawing. The Earth is about the size of one of the Sun's average sunspots, and if you were to link sizes to relative distances between planets you would have to have a drawing with long extensions that would make the spacecraft unworkable. The drawing of the sailing boat on its side reappears in the background behind the drawing of the man and woman. It is meant to show relative sizes and explain that the size of Pioneer 10 could be used to help visualise the size of grown humans. However the convention of overlapping forms in a drawing to represent one thing being in front of another is a very sophisticated one, one not learnt by humans until quite a late stage in their educational development. The idea that you can leave gaps in a form to suggest it sits behind other forms is usually only learnt if you go to schools that teach drawing from a Western European perspective. The fact that the Pioneer spacecraft is visualised from one specific point of view is also something only understandable if you follow engineering drawing conventions of plans and elevations. So lets hope the drawing is first seen by an extra-terrestrial engineer. 


A photograph of Pioneer 10, showing the plaque in place

It may well be that an advanced extra-terrestrial being would be able to visualise whole cultures and species types by analysing patterns of making revealed in the making of any object and that by looking at the way the Pioneer was engineered would be able to deduce the evolution of the creatures that built it. If so it could also be important to this creature to provide for itself an aesthetic framework within which to view this new knowledge. Because of its own evolutionary history it might well take a deep interest in insect or crustacea evolution and accompanying structural and aesthetic possibilities and decide that all terrestrial evolution is based on the structure of a flea or shrimp.

Robert Hooke: Drawing of a flea: 1665

Diagram of Evolutionary links that suggests that evolution from a distance is very shrimp like

It is most likely that this alien creature will have evolved in such a way that it understands itself as part of an always changing set of relationships. It will be aware of beginnings, middles and ends of these relationships and that all beginnings and ends are simply moments between changing patterns. The idea that we could communicate with this creature was one you would expect a well known scientist like Sagan to have thought through a little more. In some ways it could be seen as quite funny, but in others it is indicative of the reason why we have managed to get the world into the state it is. As we have come to understand some of the complexities of the physical world, to the extent that we can send a spaceship out into the void, we have at the same time not been able to understand how blinkered our view of ourselves and others is. We designed those figures on that plaque with a certain presumption, one that is beginning 45 years later to unpick itself.  At the same time that many humans are shaving themselves everyday to become hairless like the drawings on the plaque, other humans are being persecuted because they appear to be neither of the two genders represented. The images of the people represented represent a view of humankind that was in fact not very kind, or was somewhat thoughtless.

In the book 'Sum: Tales from the Afterlives', David Eagleman recounts forty stories, each one describing a different afterlife. In his short story 'Microbe'  he gives an account whereby God is discovered to be the God of microbes.



"There is no afterlife for us. Our bodies decompose upon death, and then the teeming floods of microbes living inside us move on to better places. This may lead you to assume that God doesn't exist—but you'd be wrong. It's simply that He doesn't know we exist. He is unaware of us because we're at the wrong spatial scale. God is the size of a bacterium. He is not something outside and above us, but on the surface and in the cells of us.

God created life in His own image; His congregations are the microbes.
The chronic warfare over host territory, the politics of symbiosis and infection, the ascendancy of strains: this is the chessboard of God, where good clashes with evil on the battleground of surface proteins and immunity and resistance".
From 'Sum' by David Eagleman

It is useful to remind ourselves every now and again that there is far more chance that alien life would be more like bacteria than humans. Artificial intelligences are being taught to learn in laboratories all over the world and the more we work with the associated software programming the more we become aware of how blinkered learning actually is. Whatever is taught to an AI becomes the world that the AI exists in and it 'sees' everything else from the point of view from whereby it was fed the initial information. But more on that in the next post.



Sum is available to download here








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