The rationale for MSU's densely populated universe
The Mapped Space Universe (MSU) is somewhat rare in space opera science fiction in that mankind does not command an all powerful galactic empire or lead an alliance of alien races, nor does it fight interstellar wars as an equal. On the contrary, in the MSU, mankind is the youngest, weakest and least technologically advanced interstellar civilization in the galaxy. It holds this position because it is a virtual certainty that that is the place the human race will one day occupy. Indeed, it should be self evident that the day mankind develops interstellar travel technology will be the day we become the most junior interstellar civilization in the cosmos.
This paper presents the rationale for a universe inhabited mostly by interstellar civilizations rather than by technologically primitive societies. It explains why intelligent life is likely to be thousands to millions, perhaps even billions of years ahead of the human race. It does this firstly by considering the astronomical evidence, then by expanding upon and explaining in detail The Hourglass Theory first presented in my novel The Mothersea. It concludes with a brief analysis of an extraordinary human-alien encounter from the 20th century that provides a remarkable insight into this topic.
Astronomical Evidence
Building Blocks
For life as we know it to exist, certain building blocks must be present. These include carbon based molecules known as nucleotides, of which DNA and RNA are composed, in addition to approximately twenty amino acids that form polypeptides and proteins. From these relatively few components, an immense variety of life has flowered on Earth, leading ultimately to the appearance of mankind (Morris 2003).
To some, life on Earth is unique, however, spectroscopic analysis indicates that these basic building blocks are completely ubiquitous throughout the universe. Where potentially habitable planets exist, they will most likely possess the building blocks necessary for life.
Quantity
Habitable planets are likely to be relatively rare compared to the total number of planets, however, the vast number of stars in the universe indicates that in absolute terms, habitable planets will be numerous. Supporting this argument is an October 2016 analysis of the Hubble deep field imagery that found there were some two trillion galaxies in the universe, ten times the number previously thought. It is generally believed that there are, on average, one hundred million stars per galaxy, suggesting there are 2 x 1020 stars in the universe (Space.com 2017). If a tiny fraction of these have habitable worlds, then the probability of the universe being densely populated is high.
Even with our relatively limited technology, the search for extra solar planets has already discovered many worlds orbiting nearby stars. Indeed, our theory of stellar formation predicts that planets should exist around every main sequence star. As of February 2018, 3,743 worlds have been discovered in 2,796 planetary systems. 625 of these systems have multiple planets (Exoplanets).
As our technology improves, these numbers will grow to millions of worlds. Of this, we may be certain.
Age
The age of the universe is the one factor science fiction unwittingly (or conveniently) ignores most of the time. We know from our study of the Cosmic Microwave Background (CMB), the radiation fossil of the Big Bang, that the universe is 13.8 billion years old, plus or minus 70 million years (WMAP). The high degree of accuracy for this number is the result of multiple space missions and many years of painstaking research.
To fully grasp the impact of this great age requires an understanding of just how great a span of time 13.8 billion years is and of what has happened during that near eternity.
Star Birth Rate
In determining the universe's capacity to sustain abundant life, we must consider its chemical evolution. At the time of the Big Bang, the universe was initially composed only of radiation. It cooled for the next four hundred million years at which time very large stars formed. Their great size limited their existence to only a few million years, but during that time, the vast fusion reactors in their cores began transforming primordial hydrogen into heavier elements through the process of nucleosynthesis. These early stars scattered their material across the cosmos, then was used again to form more stars that continued the nucleosynthetic process of producing heavier and heavier elements.
We should also understand that very high quantities of heavier elements are not necessarily a good thing. There is a point beyond which too many heavy elements can reduce the potential for life by, for example, producing too many gas giants in a system that could disrupt the orbits of smaller terrestrial planets (GHZ).
During this early period, life as we know it could not have existed. The molecular building blocks necessary for life and the heavy elements required for terrestrial planets to form did not yet exist in sufficient quantities. It was an expanding universe filled with swirling clouds and giant stars explosions that were chemically evolving the universe toward a point where life could take hold.
Five hundred million years after the Big Bang, the first galaxy formed, then half a billion years later, the large scale structure of the universe took shape. This structure is formed by the distribution of matter on a cosmic scale. It is composed not merely of stars and star clusters, but of galaxies and the gaseous material drifting between them. Its appearance is distinctive and web like, and is our true home as seen from a great distance.
Large Scale Structure of the Universe
(Room)
Type Ia supernovas appeared about a billion years after the first stars formed, accelerating the process of star formation by scattering their material in massive stellar explosions. Toward the end of the second billion years after the Big Bang, star formation across the universe reached a peak, then steadily declined. It was originally thought this peak occurred around three to four billion years after the Big Bang, but this estimate was recently reduced. Today, new stars are forming at about 3% of the rate that was occurring approximately twelve billion years ago. The reason for this decline is that over time, the primordial gases used in star formation were consumed, clearing the universe of the basic material required for new stars to appear.
Star Formation Peak
(University of Virginia, Star History)
We now know that 95% of all stars that will ever form in the universe have already come into existence. For the remaining life of the universe, likely to be a period spanning tens of billions of years, only 5% more stars will ever form. Our own Milky Way will contribute to new star formation for a while, although many galaxies and star clusters no longer do (Star Formation).
We should treat the Star Formation Peak (SFP) and curve as a lead indicator, pointing the way to what follows billions of years later. Intelligent life would appear long after the Big Bang plus two billion years in proportion to the available habitable worlds existing in the universe, which is a function of star formation. It is, therefore, suggested here that star formation indicates the relative rate of appearance of intelligent life in the universe.
The corresponding lag indicator, which we may call the Intelligent Life Appearance Peak (ILAP) is the high point in the emergence of intelligent life in the universe. It sits upon a curve of similar shape to the star formation curve. The curve peaks at the ILAP, then the appearance rate declines over time as the availability of habitable worlds decreases. The ILAP would occur billions of years after the SFP. It is something of a statistical concept in that it relies on the immense total population of stars in the universe to be meaningful. Results may vary for smaller, subset populations (e.g. G type stars only or K type stars only), although the general shape of the curve should be consistent.
Cosmic Deep Time
Comprehending the immense time scales involved in understanding our position in the universe is a great challenge. In geology, the problem is referred to as understanding ‘deep time’ (Geoscience), comprehending timescales so large as to be meaningless to the human mind.
Earth is 4.6 billion years old, but how many people really understand just how great a span of time that is? How can they, when humans live for less than a century and human civilization has existed for less than ten thousand years? The order of magnitude differences between our frame of reference and geologic time are immense. From the astronomical perspective, the problem is amplified because we are considering cosmic time scales far greater than the mere age of planet Earth.
From the geological deep time perspective, the evolutionary process on Earth has been reset globally five times by major mass extinctions, and a number of times on a small scale by minor extinction events. Mass extinctions are important because they not only destroy existing life, but also clear the way for new mutations to fill evolutionary windows vacated by extinct species.
The following diagram illustrates just how many evolutionary periods have existed on Earth and the vast spans of time they occupied. Consider the millions and billions of years that have passed prior to the appearance of Homo sapiens 200,000 years ago, appreciating how tiny our span of existence has been relative to what came before.
Geologic Time and Mass Extinctions
It is possible that without one mass extinction, intelligent life may have evolved on Earth much earlier than it did. Imagine if the dinosaur killer asteroid and associated volcanic activity had not occurred 65 million years ago. Would an intelligent species have evolved from the dinosaurs 50 million years ago? If so, that (dino)Saurian intelligence might now rule a 50 million year old interstellar civilization that is currently studying technological primitives on a distant world as they dream of a future among the stars.
On many other worlds more fortunate than Earth, one less mass extinction may have been enough for its inhabitants to reach the stars millions of years before the appearance of Homo sapiens. 12.8 billion years have passed since the formation of the large scale structure of the universe to the dawn of man (see the illustration below). In all that time, much has happened.
History of the Universe
Let us now enter a thought experiment, seeking to understand what might have transpired before mankind emerged on the plains of Africa.
The Hourglass Theory
We come now to the Hourglass Theory I first proposed in my novel, The Mothersea. Being a novel, I could only lightly touch upon its meaning, so I will now take this opportunity to present a more detailed explanation.
The Hourglass Theory considers the appearance of intelligent life across the universe as an evolutionary continuum (i.e. a continuum of appearances). It assumes life emerges in near infinite variety at almost infinitely different times and places, moderated by the rate of star formation and the enrichment of the chemical composition of the universe via nucleosynthesis.
No two intelligent species are likely to appear at the same time in close proximity to each other, although star forming regions do produce stars of similar age, so a simultaneous appearance is not absolutely impossible. Varying rates of evolutionary progress and mass extinctions would, however, make it extremely unlikely. It is more probable that if two intelligent species appear in the universe at the same time, they will be separated by vast distance, perhaps millions or billions of light years.
The hourglass divides the evolutionary path of all intelligent life into three stages, represented by the two large bulbs and the narrow neck of the hourglass that joins them. Each stage represents unequal spans of time. In the first diagram, the hourglass is on its side.
The Ascent Stage
The Ascent Stage follows on from a long period of evolution from single cell life to complex, non intelligent life forms. On Earth, this evolutionary process took at least five hundred million years. The Ascent Stage begins with the first spark of intelligence. In mankind, this period began 3.4 million years ago (mya).
The Hourglass Theory assumes that intelligence evolves at different times and at varying rates across a multitude of worlds. Mass extinctions would kill off, slow or accelerate some species, depending on their particular circumstances, further randomizing progress. The universal constant is near infinite diversity.
The Ascent Stage represents the period of hunting and/or gathering before civilization. It is a time defined by minds increasingly capable of imagining ideas, of creating language, superstitions, myths, of constructing primitive tools and weapons and developing social structures. These infinitely varied minds become increasingly active as they learn to master their environments with mental power rather than physical strength.
The Ascent Stage ends when a species has developed sufficient intelligence and social organization to found civilization. On Earth, this occurred approximately 8000 years ago.
The founding of primitive civilization is a turning point because it allows primitive people to produce and store surpluses, which in turn allows knowledge to flourish, industry to begin and invention to accelerate. It marks the end of nomadic existence and the dawn of a more complex, sedentary way of life.
The Transition Stage
The Transition Stage is represented by the neck of the hourglass. It is a period of incredibly rapid progress, from the first primitive agrarian civilization to the development of interstellar travel. For mankind, this transition appears likely to be accomplished in less than ten thousand years. This relatively short span of time, following on from the multi-million year Ascent Stage, and the hundreds of millions of years of instinctual evolution before it, is a critical factor against peer interstellar civilizations emerging in close proximity to each other.
Ten thousand years seems a great expanse of time to us, considering it encompasses all recorded human history, yet in terms of cosmic deep time thinking, it is scarcely a moment.
Two thousand years ago, Rome ruled the ancient western world, China flourished in the east and hunters and gathers roamed the Americas and Australia. Now, an instant later, electrified cities glowing with light span the world and the mysteries of the universe are unraveling before our eyes. Compared to the age of the universe, this is progress at astonishing speed.
From the perspective of cosmic deep time thinking, we may conclude that the transition from no civilization to one able to reach the stars occurs explosively fast. To us, with our distorted time sense, it seems painfully slow, but that is only a question of perspective, not reality.
While interstellar travel is still far beyond our existing technology, I suggest in the Mapped Space Universe that mankind will have unlocked the required technology within the next five or six hundred years. Looking at our current rate of progress, this is not an unreasonable estimate, although considering the enormous technological challenges involved, it may well take longer. For mankind in the fictitious MSU, the Transition Stage was completed in a mere eight and half millennia, a veritable sprint compared to the cosmic time frame.
Considering the speed with which a species passes through this phase, it is remotely possible that the human race may be the only species in the entire galaxy currently at this stage of development. If there are others, they will be relatively few in number compared to the total population of interstellar civilizations.
The Interstellar Stage
While the notion of countless interstellar civilizations appearing over billions of years may seem a little overwhelming, the truly startling consideration is how advanced, how old they must now be. Unless they have inexplicably disappeared, tragically destroyed themselves or departed for other universes unknown, they are still here, a near infinite number of societies ranging from thousands to billions of years ahead of us.
Once an intelligent species appears, barring some calamity, it will continue, using all its genius and creativity to ensure its survival. After all, the desire to survive is perhaps the most fundamental impulse of all. This is why the Interstellar Stage is the longest by far and why the end of the hourglass is open to infinity.
We now consider the hourglass from two perspectives.
1. The Cosmic Hourglass
The Cosmic Hourglass shows the distribution of intelligent life in the universe at a point in time. Each civilization is like a grain of sand, shown by its position within the three stages of the hourglass. This is the version presented in The Mothersea.
In the diagram below, time is the key factor. Firstly, there is the time required to pass through each stage of the hourglass, and secondly, there is the total elapsed time since intelligent life first appeared in the universe. For the first temporal factor, the three stages span millions, thousands and billions of years for the Ascent, Transition and Interstellar Stages respectively. For the second temporal factor, the baseline assumption for this illustration is that intelligent life first appeared one billion years ago, although it is possible this may have occurred earlier or later.
The distribution of intelligent life across the hourglass should be viewed from the perspective of temporal magnitude, i.e. the relative order of magnitude of the time spent by each civilization in each stage. The order of temporal magnitudes are 5 x 10^6, 1 x 10^4 and 1 x 10^9 years respectively. The relative time spent in each stage as a proportion of the total time intelligent life has ever existed in the universe is calculated as follows:
Ascent Stage (Evolving Intelligence) = 5 million years / 1 billion years = 0.5%
Transition Stage (Acquiring Knowledge) = 10 thousand years / 1 billion years = 0.001%
Interstellar Stage (Interacting and Participating) = 1 - 0.5 - 0.001 = 99.499%
The Evolving Intelligence time frame was rounded up to 5 million years from mankind's more rapid 3.4 million years, while the Acquiring Knowledge time frame was rounded up to ten thousand years. Both are more conservative numbers than demonstrated by mankind's own progress (i.e. because of their longer duration).
Considering the very long baseline duration since it is assumed intelligent life first appeared and the relative rapidity with which species pass through the first two stages of the hourglass, these proportions are indicative of the general distribution of intelligent life in the universe, i.e. the vast majority are in the Interstellar region of the hourglass. The sensitivity analysis below shows this general proposition is valid across a wide range of baseline time frames.
This shows that even if the baseline duration of the existence of intelligent life in the universe was substantially shorter than one billion years, the proportion of interstellar civilizations as a percentage of all intelligent species remains very high. The human race would need to be among the first intelligent life forms in the universe for this general proposition not to be true. Considering the arguments stated above, this is extremely unlikely. On the contrary, this author considers a one billion year baseline time frame to be a conservative assumption.
The inherently linear nature of these calculations should also not be a significant, distorting factor because the baseline duration is so large relative to the first two stages, it offsets other variations. This makes the Cosmic Hourglass a flexible conceptual tool able to model a range of assumption sets.
Only one civilization marker is shown in the neck of the hourglass to illustrate the possibility that mankind may be the only civilization in the Transition Stage within the Milky Way Galaxy. From a universe-wide perspective, there are likely to be many species, perhaps millions, in the Transition Stage. Even so, as a proportion of the total, this quantity will be close to 0% due to the immense quantity of intelligent species likely to have appeared over time.
The lower bulb of the Cosmic Hourglass shows the effect of eons of interstellar civilization, with a clustering of mature species toward the bottom. In the Interstellar Stage, there are noticeably less civilizations in the upper (i.e. earlier) area than the lower (i.e. later) area because that earlier area is transited over time. As new interstellar civilizations pass through the upper area, they develop broad interactions with other civilizations and increasingly participate in the collective management of interstellar affairs. The traffic jam at the bottom of the hourglass assumes that at some point, a peak level of knowledge is acquired. This is where all the laws of nature have been mastered and further advance becomes extraordinarily difficult. After all, how does one advance beyond knowing everything?
In the early part of the Interstellar Stage, young civilizations find themselves vastly inferior to the established galactic powers and must pass through a long period of adjustment as they learn to adopt cosmic normative behavior. If such a thing as galactic citizenship exists, it is unlikely to be granted to new civilizations until they have learned the rules of the road and shown they can be trusted.
The Mapped Space Sirius Kade space opera books are set in this early adjustment period of the Interstellar Stage, while the earlier MS-First Contact books are set in the Transition Stage, where nothing is known of galactic civilization except what falls unexpectedly from the sky.
Both ends of the hourglass are open. This reflects the inflow of new species evolving intelligence in Stage One (at the top of the hourglass) and the outflow of super species in Stage Three (at the bottom). A super species is one that no longer accepts interaction with (from its perspective) relatively primitive interstellar civilizations or participates in the governance of matters which no longer interest it. Of course, super species may also choose to remain in charge and engaged, while communicating to young interstellar civilizations through lesser, intermediary societies, although in the Mapped Space Universe, there are clear signs of disengagement.
In the Mapped Space Universe, Observer civilizations are those at the very bottom of the Cosmic Hourglass, who remain involved in galactic affairs. In the book The Mothership, the species identified simply as one of ‘the First’ had passed out of the Cosmic Hourglass altogether. It accepted contact from an Observer civilization in Earth’s 21st century, but by the 47th century, its whereabouts had been unknown for over a thousand years. This deliberately ambiguous treatment reflects the reality that such civilizations may not explain themselves to greatly inferior forms of life.
We now consider the second conceptual hourglass model which looks at the appearance of intelligent life over time, rather than at a point in time.
2. A Universe of Hourglasses
The Universe of Hourglasses is a map of each civilization’s progress from hunter and/or gatherer to interstellar traveller. Whereas the Cosmic Hourglass views the position of civilizations from a fixed point in time, the Universe of Hourglasses shows the position of each civilization within the cosmic time continuum. It does this by charting each civilization against:
i) the cosmic history of the universe, and,
ii) its relation to every other civilization in the universe (past, present and future).
From this viewpoint, there are as many hourglasses as there are intelligent species in the universe.
The Star Formation Peak lead indicator is based on the population of all stars in the universe. For the Intelligent Life Appearance Peak lag indicator and curve to be more accurately mapped, determining when Population I star formation peaked would be required (rather than using all stars). Population I stars like our sun have the highest content of heavy elements and are most likely to have habitable, terrestrial worlds with life. Accuracy determining the Intelligent Life Appearance (ILA) curve could be further improved by focusing on the star formation rates of specific types of Population I stars (e.g. G and K type stars).
It is difficult to estimate how long ago the ILAP occurred, but it is not unreasonable to suggest it could be anywhere from 500 million to several billion years ago. Assuming the ILA curve follows a decline comparable with the star formation curve, the ILAP's placement in time will determine our position on the ILA curve. To illustrate the possibilities, two scenarios are presented, an early and a late ILAP.
It should be noted that the star formation curve, from peak to the present day, spans a period of almost twelve billion years. Considering the ILAP and ILA curve lags billions of years behind the star formation curve, we may conclude that we are not yet at the later stages of Intelligent Life Appearance. Nor, however, are we at the early stages, but somewhere in-between.
Scenario 1 - Early ILAP
This scenario probably places the Intelligent Life Appearance Peak at too early a stage in the universe's evolution. It shows what the ILA curve would look like as fewer and fewer habitable worlds remain, and only a small number of intelligent species are appearing. If the ILAP appeared long ago, then mankind is now at the tail end of the curve. More likely, this is how the ILA curve will look billions of years from now.
Scenario 2 - Late ILAP
This scenario places the Intelligent Life Appearance Peak at least twelve billion years after the Big Bang, ten billion years after the Star Formation Peak. It shows a universe where no intelligent life existed for many billions of years. Subsequently, a large proportion of species appeared, perhaps more than half the number that will ever exist in the universe. Mankind is shown after the ILA Peak, appearing as the curve is in steep decline, the only species in the Transition Stage, while three primitive species are included in the Evolving Intelligence Stage. This scenario depicts mankind as appearing somewhere in the middle of all possible intelligent life forms that will ever be, including those yet to evolve. It shows many civilizations have already reached the stars over the preceding hundreds of millions, perhaps billions of years. Of the two scenarios, the Late ILAP scenario is the more likely.
The obvious conclusion is that most existing civilizations in the universe predating mankind’s hourglass have already achieved interstellar civilization status, and did so long before Homo sapiens appeared. While this may seem an outrageous claim, cosmic deep time thinking indicates it is, perhaps, the only rationale conclusion.
We now move on to a topic which supports the ideas presented here, although many will reject it out of hand. Nevertheless, I include it here for completeness. It is perhaps the most famous of all human-alien encounters.
The Betty and Barney Hill UFO Case
The fascinating UFO contact case of Betty and Barney Hill is unusual in that it contains astronomical information from which we may infer some realities about our stellar neighborhood. The value of this information is enhanced by the fact that neither individual had the requisite astronomical knowledge to fabricate the data.
Betty and Barney Hill claimed to have been abducted from rural New Hampshire, USA, on 19-20 September, 1961 by aliens from Zeta Reticulum (Hill UFO Case). Zeta Reticulum is a wide binary system 39.17 light years from Earth comprising a G2 star similar to our sun and a slightly smaller G3 type star. These stars are 0.06 light years apart (3750 AU), about as far as Pluto is from our sun. That is far enough apart for both stars to have planetary systems (Zeta Reticuli).
After the encounter, the Hills were subjected to intensive questioning. Their stories were found to corroborate and there was no evidence of deception. Nuclear physicist and UFO researcher Stanton Friedman interviewed them in detail and concluded that they were credible witnesses (astronomy.com).
In 1964, while under hypnosis, Betty Hill drew a picture of a three dimensional map she’d seen while aboard the alien spacecraft. There were many stars on the map in the alien craft, but Betty was only able to recall the major stars connected by lines which were described to her as ‘trade routes’. The map she saw had no indicator of scale.
Betty Hill's original hand drawn map
In 1966, amateur astronomer Marjorie Fish began studying Betty’s map. After much effort, she was able to manually identify the stars using an ingenious system of strings of beads to replicate the three dimensional nature of space. Her work was validated years later by a computer simulation.
Betty Hill’s Star Map, Fish Map, Computer Map
(Astronomy.com)
It is this map that created the idea that at least one group of extra terrestrials visiting Earth originate from Zeta Reticulum. The major stars on the map have been identified below.
Hill Star Map
(Dickinson)
Each of the stars linked by ‘trade route’ lines and other prominent stars are listed below by type, distance from Sol, and solar mass (i.e. size as a proportion of our sun). Some have since been found to have extra solar planets orbiting them.
On the original Betty Hill map, the trade route lines between Zeta 1 and Zeta 2 were drawn multiple times, perhaps indicating a greater flow of interstellar traffic between those two star systems than with other star systems. Considering the close proximity of the two stars to each other, and their similarity in size to our sun, one may speculate that the original Zeta Reticulum inhabitants might have evolved on a world around either star, colonized their origin system then their nearby binary partner system. Colonizing the binary partner system might have been done with sub-light propulsion technology, allowing the Zeta Reticulum Civilization (if it exists) to populate two systems before the technology for a true interstellar civilization had been acquired.
Zeta 2 Reticulum is a G2 type star like our sun and is very close in size to it (98.5%). It is also the only star with a line drawn across it, perhaps signaling it is of unusual importance. In mankind's far future, our star charts will surely mark the Sol System as being of unusual significance to us because it is the location of our homeworld. We may wonder if the marking on the Hill Star Map is not a similar indicator, marking their origin system?
In considering the known stars on the map, we should note the proliferation of G and K type stars. Main sequence versions of these star types have life spans of 15-30 billion years for K types and 10 billion years for G types, while F types last only 2-4 billion years. The K and G types have life spans long enough to permit intelligent life to evolve. Considering the shorter life span of F type stars, the odds of an interstellar civilization appearing in an F type system would be less than for K and G type star systems. However, it is possible that an F type star system might be colonized by an existing interstellar civilization, raising its status.
Of the three prominent stars not connected by trade routes, all are beyond fifty light years from Earth and one (Gliese 86.1), is an orange to red giant, and is therefore approaching the end of its life. While that system might still be inhabited, one would assume, if an interstellar civilization had once evolved there, it has moved its population elsewhere by now. The other two stars in this group, both G types, might hold civilizations, which is why they are on the map, but the lack of trade routes may suggest the Zeta Reticulans do not interact with them on a regular basis.
What relevance this map holds in relation to the Hourglass Theory is this simple observation. The eleven trade route systems – i.e. inhabited systems – are all within 50 light years of Earth. This is a relatively high number of inhabited systems within quite a small stellar radius and supports the case for a densely populated universe.
There are approximately 1,000 stars within 55 light years of Earth. If the Betty Hill Map can be believed, 11 of those are inhabited. If this tiny sample is in any way representative of the universe, we may dare to speculate that 1.1% (i.e. 11/1000) of stars are inhabited, with an obvious focus upon G and K type stars. Estimates of the number of stars in the Milky Way Galaxy range from 100 billion to 400 billion, although not all of these are in what we may consider to be the Galactic Habitable Zone. This zone is that part of the galactic disk beyond the radiation filled core, and inside the outer periphery where heavier elements are less common. It is that part of the galaxy where life is most likely to exist, a goldilocks zone on a galactic scale, although its habitability can be disrupted by cosmic events such as supernovas and gamma ray bursts.
Galactic Habitable Zone
(GHZ)
Considering the difficulty in obtaining generally accepted values for the type and quantity of stars in the various parts of the galaxy, let us arbitrarily halve the minimum number of stars in the galaxy to obtain a possible number of stars within the Galactic Habitable Zone (to which the Hill Star Map ratio relates). Halving eliminates zones within the galaxy that are less likely to hold life, such as the radiation filled core and those regions where there are less heavy elements, such as the outer periphery of the disk, the stars above and below the disk and in the halo. The intention is to understate (i.e. to take a conservative view) of the feasible population of stars that might hold life. Let us now use this number (50 billion) to illustrate what the Hill Star Map ratio implies for the quantity of inhabited worlds in the galaxy .
Inhabited worlds = 1.1% x (50% x 100 billion) = 550 million.
Using this number of inhabited worlds and the ratio calculated for an hourglass baseline of 1 billion years above, this places 5,500 civilizations in the Transition Stage of the hourglass presently occupied by mankind compared to 547 million interstellar civilizations as follows:
​
Ascent Stage Civilizations = 0.5% x 550 million = 275,000
​
Transition Stage Civilizations = 0.001% x 550 million = 5,500
​
Interstellar Stage Civilizations = 99.499% x 550 million = 547,244,500
​
Even using the minimum 100 million year baseline, which is almost certainly unrealistically short, there would still be over half a billion interstellar civilizations in the Milky Way Galaxy (i.e. 522 mil).
Complimenting this illustration is an analysis of Kepler space mission data that estimated that at least 17 billion Earth sized worlds exist in the Milky Way, i.e. thirty times the number of worlds calculated above. This was based on research indicating that many red dwarf stars have planets and at least 17% of all stars in the galaxy have at least one planet between 0.8 and 1.25 times Earth's mass (Kepler).
It is also interesting to note that Gowanlock et al 2011, in a sophisticated computer simulation, predicted that between 0.3% and 1.2% of all stars in the galaxy could contain at least one planet capable of supporting complex life (i.e. 300 million to 1.2 billion). This suggests that the Hill Star Map's 1.1% is not entirely beyond the realms of possibility, especially considering the Gowanlock study considered the galaxy as a whole, rather than focusing on a favorable region within the Galactic Habitable Zone such as our own Orion Arm. Narrowing the sample population to the GHZ would increase the upper and lower limit percentages, moving the Hill Star Map ratio toward the mean value.
These studies suggest that whatever the actual number of inhabited worlds in our galaxy is, it will be, dare I say it, astronomically high.
This is simply a thought experiment extrapolating a scrap of information that may or may not be true. The numbers shown are for illustration purposes only, yet if the Hill Map is indicative of reality, then it supports the contention that we do indeed inhabit a densely populated universe. We just don’t know it yet.
Conclusion
Synthesizing astronomical, chemical, geological, evolutionary and even UFOlogical knowledge into a proposition about man’s place in the universe is a hypothetical exercise, but perhaps not a fruitless one. If the conclusions expressed here are correct, man’s understanding of his place in the universe may yet undergo the greatest transformation of all, the cosmological transformation.
These ideas are the basis for man’s place in the Mapped Space Universe, which for all its dangers, is also a place ripe for opportunity. This is because the more advanced a civilization, the more value it places upon law, morality and ethics, generally speaking, although there are no absolutes. Even though mankind may be late to the interstellar community, those who have been there longer than we have existed will allow us our place, because to deny us would be unjust.
And justice matters.
This proposition is not based on wishful thinking, but on the simple fact that great civilizations able to stand the test of time are built upon great principles. If this were not true, they would not have survived.
And therein lies our hope for the future.
References
The Hill Star Map interpreted by Marjorie Fish
Geoscience
Deep Time, the geological time scale.
Gowanlock, et al 2011.
'A Model of Habitability wihtin the Milky Way Galaxy'
Morris, Simon Conway 2003,
"Life's Solution", Cambridge University Press
Room,
'How many stars are there?'
WMAP
NASA’s Wilkinson Microwave Anisotropy Probe
Zeta Reticuli
'The truth about Zeta Reticuli'
Star Formation
SciTechDaily, 'Star Formation in the Universe has decreased drastically'