The View of the Universe from a Polar Continent
Recent research into Martian paleoclimatology has suggested that, long ago in the past (3.5 to 3.7 billion years ago — about the same time life was getting started on Earth), the northern hemisphere of Mars was covered in a great ocean. For obvious reasons, this conclusion is far from definitive; when we eventually get to Mars and are able to conduct field research on the Martian surface, we will construct a much more detailed and fine-grained history of the Martian climate, but this must wait for future research on Mars.
One of the interesting features of the projection of Mars’ past climate is that the northern hemisphere is almost entirely ocean while the southern hemisphere is almost entirely a land mass. Ocean/land mass configurations not unlike this have occurred on Earth as well, as Earth is geologically active such that its land masses move over the surface. About the same time as the Cambrian explosion, most of Earth’s land mass was in the southern hemisphere and most of the northern hemisphere was water.
The exclusively polar distribution of landmasses on a planet would have interesting consequences for any observers inhabiting these landmasses. A landmass (or several land masses) spanning the equator of a planet would allow for viewing the sky of both the northern and southern hemisphere, but an exclusively polar landmass would mean a view of only the northern or southern hemispherical view of the sky, and this would mean seeing only half of the cosmos.
Over the scales of time relevant to civilization (i.e., intelligent agents coordinating their observations), plate tectonics will not affect the location of land masses on the surface of a planet, so for the purposes of the intelligent progenitors of a civilization, the surface of a geological active planet like Earth and a geological inactive planet like Mars are indistinguishable in respect to the matter here under discussion. If a civilization managed to endure to become a billion-year-old supercivilization, then plate tectonics would become relevant to its view of the cosmos.
Because a star and its planets form from the same protoplanetary disk, the initial angular momentum of the swirling protoplanetary disk is imparted to the star and the planets means that all orbit and spin in the same direction (unless they are knocked off-kilter by a subsequent collision). This means, in turn, that a polar view is consistently oriented in the same direction as the poles of the parent star and relative to the orbital plane of the planets. If you are standing at or near the pole of a planet, and you can only stand at or near the pole of the planet, you would only be able to see one half of the universe. What would be the consequences for a civilization that developed on a world with a polar continent and a view of only one half of the sky?
Any early civilization on such a world would invent boats and shipping, but this shipping trade would be largely confined to coastal waters. With no major land masses in the uninhabited hemisphere, any expeditions sent out into the hemispherical ocean would either turn around without having found anything, or they would be lost in that great ocean. There would, or course, be sailors’ stories of a different night sky, but sailors always tell fantastic stories of the sea, and these stories would be largely unbelieved for the better part of the history of such a civilization.
In the case of terrestrial history, human beings didn’t have reliable methods for navigation at sea until the Harrison Chronometer of 1761 — nearly as far along in history as the industrial revolution. In other words, most shipping for most of history took place without accurate measurement of longitude. If a similar level of technological development would be necessary to any civilization before it could map an uninhabited hemispherical ocean, most of that civilization’s history would pass without (scientific) knowledge of this ocean, hence also without any kind of scientific knowledge of the night sky (hence the stars) of the uninhabited hemisphere.
Moreover, even once a civilization could navigate with confidence in a hemispherical ocean, there would be no land masses on which to build a telescope. One could imagine that the scientists of such a civilization would eventually try to build a barge sufficiently large and stable on which a large telescope could be placed. This would be a large and expensive project, and therefore difficult to fund. One could conduct astronomy from aircraft, as is now being done (e.g., SOFIA), but this would obviously have to wait until sufficiently large and stable aircraft had been developed.
For such a civilization on such a planet, the accidents of cosmological history that oriented that civilization to a single view of the cosmos might well have significant consequences for the development of knowledge of cosmology, and thus also for the development of principles and concepts by which the intelligent progenitors of the civilization would come to understand themselves. For example, if the planetary system were near to the center of a spiral galaxy and faced the galactic center, it would have a view of a dense mass of stars and little else; if the planetary system were at the far edge of a spiral galaxy and faced outward, it would have a view of emptiness and little else.
This civilization might be in a galaxy a lot like ours, but would (initially) formulate a conception of the universe that extrapolated from this non-representative view of the cosmos. And as a result, it would be more difficult for such a civilization to formulate concepts like the cosmological principle, or to extrapolate the Copernican principle beyond its homeworld. Once a civilization became spacefaring, and it could place telescopes in orbit, the universe entire would be revealed to it, and this might be more of a paradigm shift than space-based telescopes were to terrestrial civilization. Just as our civilization will always carry with it the imprint of our earliest history on our homeworld, so too with a civilization with a one-sided view of the cosmos.
For a civilization confined to a homeworld with a unidirectional view of the cosmos there could be advantages and disadvantages. If a massive gamma ray burst were to hit the planet on the ocean side, the civilization would be protected by the bulk of its homeworld, though it would skill have to reckon with the damage to marine ecosystems. If, on the other hand, a directional signal from another civilization on another world were to fall in the middle of a hemispherical ocean, it is likely that it would never be noticed. How a civilization is positioned in the universe, then, could play a decisive role in its development, for good or for ill.
The “local” conditions under which a civilization develops — and here I mean “local” in a cosmological sense, in which one might speak of our “local” galaxy or our “local” supercluster — may differ significantly from the “global” conditions of the universe, and the greater the divergence between the cosmologically local and the cosmologically global, the greater the difference between the universe observed from some local vantage point and the actual conditions of the universe that obtain. For those observers that exemplify the principle of mediocrity, the universe is observed much as it is, but for those observers who, as an accident of cosmological history, are perched on a vantage point that gives them a non-representative view of the universe, getting a “global” view of the universe will be difficult. How, then, do we know which one we are? That is to say, is our perspective on the cosmos representative or non-representative?
I have here constructed a thought experiment of a possible civilization that would have a non-representative view of the cosmos. Our particular cosmological circumstances means that terrestrial civilization did not labor under the difficulties that would dog an exclusively polar landmass homeworld, but, on a much larger scale, we cannot yet know if our understanding of the cosmos is representative or non-representative. If our universe is part of a much larger multiverse, as long as we are incapable of observing the multiverse will be have a one-sided view of the cosmos entire.
Originally published at geopolicraticus.tumblr.com.
