http://www.huffingtonpost.com/2013/06/03/earth-center-milky-way-astronomers_n_3380161.html?ref=topbarEarths position in the galaxy -change in opinion
SPACE AS AN OCEAN
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| PHOTO : NASA |
LESSONS FROM THE AGE OF EUROPEAN MARINE EXPLORATION FOR THE SPACE AGE.
From the Book "PROTOCOLS" (c) 2012 by American Admiralty Books
Space as an Ocean: 6/5/2013 an update
SPACE AS AN OCEAN
LESSONS FROM THE AGE OF EUROPEAN MARINE EXPLORATION FOR THE SPACE AGE.
From the Book "PROTOCOLS" (c) 2012 by American Admiralty Books
YODA WHERE ARE YOU
What is the real likelihood that we'll meet intelligent life out there?
Editor's Note: We first published this essay as part of a serial E-book about a year ago. The entire first rough draft of the book may be read in the "MARITIME LITERATURE SECTION" just scroll down past the book reviews. Recently the Huff Post Science Section published an article titled " 'ALIEN EARTH' STUDY SUGGESTS MILKY WAY GALAXY HOLDS 45 BILLION EARTH LIKE PLANETS". When we published the essay below our definition of "Earth Like" was quite different from the author of the above referenced article, Mike Wall who apparently first posted it on Space.com .
The planets the study refers to as "Earth Like" are simply somewhat near earth sized, with orbits around their sun that are roughly similar to Earth's. The study doesn't reveal anything about these planets rotation about their own axis or changing pole orientation which cause the day night and seasonal aspects of our own climate, nor do these studies indicate that any of these planets even have atmospheres. Most of these "new planets" are "estimated" planets meaning that they haven't actually been sighted but are estimated to exist based on a sampling of similar stars studied that had such planets. These "new"earth like" planets are products of statistical analysis and subject to all of the errors inherent in statistical projection using small samples.
These "new" planets are not revolving around yellow suns like our own but around "Red Dwarf" stars with surface temperatures roughly in the 2,000 degree Fahrenheit range cooler than our sun. Obviously, there will be some differences in types of radiation coming off a red dwarf as well as the radiant heat difference. There is no mention of the presence of moons or large outer "guard planets" as exist in our solar system to reduce the frequency of impacts with meteors and comets, there can't be, these "new planets" are not observed but products of statistical analysis. Finally as we observed in our original analysis we exist on an outer radial arm of our spiral shaped galaxy, a uniquely comparatively tranquil place in the galaxy in terms of meteors, comets, asteroids, and other naturally occurring space objects that can and do impact planets. By contrast the inner parts of the galaxy are a much more violent place.
Even if evolution had more time there as the report suggests, it is the time between massively destructive events that count. One of these objects whacked the dinosaurs which gave mammals a shot at reaching the apex of the biomass, but we had enough time between celestial body bombardments to evolve. For that to happen in the center of the galaxy the "earth like planet", and by that we mean a lot more than just roughly size and orbit distance from its star; would have be positioned in a unique solar system with an extraordinary collection of "outer guard planets". When we published our estimate of the chances of another space traveling civilization in our galaxy we based it on a much closer definition of "Earth Like". We don't think this latest study and statistical projection change our estimate of the chances of industrial and space-faring civilizations at all. Though subject to all of the potential error inherent in small sample statistical analysis, the study does suggest that the probability of at least microscopic life is higher than previous estimates and possibly not confined to planets circling yellow suns at the thought to be, appropriate distance.
A link to this report on the latest estimate of "Earth Like" planets in our galaxy is posted below, just remember "Earth Like" has different meanings in different contexts. In this latest study it refers only to relative mass, composition, and distance from the star orbited. Below the link is a reprint of our original posting, and below the reprint of our original posting are extracts from this latest study with comments from the author of our posting.
http://www.huffingtonpost.com/2013/02/06/alien-earth-milky-way-galaxy-earth-like-planets_n_2631063.html
YODA WHERE ARE YOU
What is the real likelihood that we'll meet intelligent life out there?
When European man first set out on the great voyages of exploration he expected to reach civilizations. He found both civilized and primitive tribal societies in abundance. Indeed the whole Earth while separated by what seemed like uncrossable seas, was in fact thickly peopled with diverse societies. Yet sea faring European man also found that much of the Earth was only thinly populated, in some cases so thinly as to be considered uninhabited. What are we likely to find in space?
Lets look at some probabilities in light of what some serious students of probability have said, based on the latest available information. For the purpose of simplicity, and keeping the discussion focused on the more immediate future, (the next couple of hundred years vice the next two thousand ) let's limit the discussion to our own galaxy. We shouldn't get beyond this area in the more or less immediate future. If there is going to be a first contact in the next two hundred years it will probably be with folks from our own galaxy.
In our galaxy which we call the "Milky Way". astrophysicist now estimate that we have about 135 billion stars. Presently most theories of stellar formation suggest that planetary systems around stars are common, perhaps the norm. We have certainly been discovering a lot of these planets of late now that we have a better idea of how to detect them from Earth or orbital observatories. Some of these planets have been found in constellations that sailors have navigated by for centuries. So lets follow the line of reasoning of Carl Sagan and some of the numbers provided by Isaac Asimov and Stephen H. Doyle and call the number of planetary systems something just a little shy of 135 billion. Lets assume that each of these planetary systems contains 6 to 12 planets. That gives us "billions and billions" (Carl Sagan) in fact , about a trillion "worlds" in the Milky Way. Now of these somewhat less than a trillion "worlds" some are circling stars much larger, smaller, colder, or hotter than ours. Some are circling twin stars and receiving radiations of sorts that we can only begin to imagine. Some have rotations that are too slow to regulate temperature decently for life, some are too near their stars, some too far. In short the vast majority aren't very Earth like. But near a trillion "worlds" is a lot of "worlds".So the law of probability makes it highly likely that some are indeed Earth like.
Stephen H. Dole and Issac Asmimov applied probability reasoning to the question in PLANETS FOR MAN (Random House 1964). and arrived at an estimate of as many as 640 million Earth like planets , at least in terms of having approximate mass, temperatures, orbit/rotation, chemistry and a sun like star to rotate about at approximate earth like orbital distance. This boils down to only one star out of every 210 has anything even similar to an Earth like planet. Only one planet out of every 4,000 is estimated to be Earth like. Now assuming 640 million Earth like, life generating planets in our galaxy, what does probability theory say about intelligent space faring life being out there? Asimov looked beyond Sagan's cataloging of "billions and billions" of "worlds" to try to estimate the actual probability of some space faring civilizations in our galaxy. Some of his reasoning can be found in THE PLANET THAT WASN'T.(Double day and Company 1976). Let's follow some of Sagan's, Asimov's and Dole's math here.
As Asimov observed , on Earth life took about three billion years to evolve to its present state . Civilization has existed for about 10,000 years. So the ratio of uncivilized years to civilized is 300,000 to 1. So if we consider Earth to be about average, and consider that life started in different times in different places it should be safe to estimate that civilization exists on 1 out of every 300,000 of these Earth like Worlds at best. According to Carl Sagan' like line of reasoning that would give us an estimated 2, 150 civilizations in our galaxy ranging in technological development from pre-Roman like to far beyond modern day America. (Notice I wrote according to the Sagan line, Asimov injects some new considerations later on.) Now looking at industrial civilization we see Earth has had one for about 200 plus years out of 2,000 years of well documented civilized life. So of our galaxy's estimated 2,150 civilizations, a likely ratio of non or pre-industrial societies to industrial societies would be 50 to 1. That leaves us with an estimated 43 probable industrial worlds out there. Not all of them will be space faring yet. So lets estimate the space farers at 21 societies, figuring ourselves to be the median.
OK, so is it probable that 21 societies in our galaxy are capable of some type of space travel? It's possible, but hardly probable based on our current knowledge. Asimov's biggest dampener on Sagan's estimate is the fact most of these planets on which we based all of the above calculations on are located in the circular portion of our spiral shaped galaxy while we are located on an outer spiral arm. The circular portion is very violent in terms of meteors, astroloids, comets and similar things hitting the planets there. The closer to the middle of the galaxy the more violent the neighborhood. Evolution needs extensive time between cosmic bombardments to evolve intelligent life. So if we ignored this basic fact in calculating a probable 21 space-faring societies in our galaxy, our estimate is wildly optimistic. Considering the facts as we think we know them today, the fact that we are here is astounding. But then the galaxy is a really big place and we truly don't know all of the facts
Lets look at some probabilities in light of what some serious students of probability have said, based on the latest available information. For the purpose of simplicity, and keeping the discussion focused on the more immediate future, (the next couple of hundred years vice the next two thousand ) let's limit the discussion to our own galaxy. We shouldn't get beyond this area in the more or less immediate future. If there is going to be a first contact in the next two hundred years it will probably be with folks from our own galaxy.
In our galaxy which we call the "Milky Way". astrophysicist now estimate that we have about 135 billion stars. Presently most theories of stellar formation suggest that planetary systems around stars are common, perhaps the norm. We have certainly been discovering a lot of these planets of late now that we have a better idea of how to detect them from Earth or orbital observatories. Some of these planets have been found in constellations that sailors have navigated by for centuries. So lets follow the line of reasoning of Carl Sagan and some of the numbers provided by Isaac Asimov and Stephen H. Doyle and call the number of planetary systems something just a little shy of 135 billion. Lets assume that each of these planetary systems contains 6 to 12 planets. That gives us "billions and billions" (Carl Sagan) in fact , about a trillion "worlds" in the Milky Way. Now of these somewhat less than a trillion "worlds" some are circling stars much larger, smaller, colder, or hotter than ours. Some are circling twin stars and receiving radiations of sorts that we can only begin to imagine. Some have rotations that are too slow to regulate temperature decently for life, some are too near their stars, some too far. In short the vast majority aren't very Earth like. But near a trillion "worlds" is a lot of "worlds".So the law of probability makes it highly likely that some are indeed Earth like.
Stephen H. Dole and Issac Asmimov applied probability reasoning to the question in PLANETS FOR MAN (Random House 1964). and arrived at an estimate of as many as 640 million Earth like planets , at least in terms of having approximate mass, temperatures, orbit/rotation, chemistry and a sun like star to rotate about at approximate earth like orbital distance. This boils down to only one star out of every 210 has anything even similar to an Earth like planet. Only one planet out of every 4,000 is estimated to be Earth like. Now assuming 640 million Earth like, life generating planets in our galaxy, what does probability theory say about intelligent space faring life being out there? Asimov looked beyond Sagan's cataloging of "billions and billions" of "worlds" to try to estimate the actual probability of some space faring civilizations in our galaxy. Some of his reasoning can be found in THE PLANET THAT WASN'T.(Double day and Company 1976). Let's follow some of Sagan's, Asimov's and Dole's math here.
As Asimov observed , on Earth life took about three billion years to evolve to its present state . Civilization has existed for about 10,000 years. So the ratio of uncivilized years to civilized is 300,000 to 1. So if we consider Earth to be about average, and consider that life started in different times in different places it should be safe to estimate that civilization exists on 1 out of every 300,000 of these Earth like Worlds at best. According to Carl Sagan' like line of reasoning that would give us an estimated 2, 150 civilizations in our galaxy ranging in technological development from pre-Roman like to far beyond modern day America. (Notice I wrote according to the Sagan line, Asimov injects some new considerations later on.) Now looking at industrial civilization we see Earth has had one for about 200 plus years out of 2,000 years of well documented civilized life. So of our galaxy's estimated 2,150 civilizations, a likely ratio of non or pre-industrial societies to industrial societies would be 50 to 1. That leaves us with an estimated 43 probable industrial worlds out there. Not all of them will be space faring yet. So lets estimate the space farers at 21 societies, figuring ourselves to be the median.
OK, so is it probable that 21 societies in our galaxy are capable of some type of space travel? It's possible, but hardly probable based on our current knowledge. Asimov's biggest dampener on Sagan's estimate is the fact most of these planets on which we based all of the above calculations on are located in the circular portion of our spiral shaped galaxy while we are located on an outer spiral arm. The circular portion is very violent in terms of meteors, astroloids, comets and similar things hitting the planets there. The closer to the middle of the galaxy the more violent the neighborhood. Evolution needs extensive time between cosmic bombardments to evolve intelligent life. So if we ignored this basic fact in calculating a probable 21 space-faring societies in our galaxy, our estimate is wildly optimistic. Considering the facts as we think we know them today, the fact that we are here is astounding. But then the galaxy is a really big place and we truly don't know all of the facts
| The Milky way our home galaxy as it would appear if viewed from overhead |
Author's notes on recent new study:
FROM: Alien Earth Study Suggests Milky Way Holds 4.5 Billion Earth Like Planets by Mike Wall published in Space . Com 2/6/2012 and the Huff Post Science Section 2/7/2016
" Astronomers have calculated that 6 percent of the galaxy's 75 billion or so red dwarfs — stars smaller and dimmer than the Earth's own sun — probably host habitable, roughly Earth-size planets. That works out to at least 4.5 billion such "alien Earths," the closest of which might be found a mere dozen light-years away, researchers said."
AAB Note: This is a study of Red Dwarfs which are significantly different from our own sun, to start with their surface is thousands of degrees cooler. "Earth sized" is a long way from being "Earth like". We think it takes a leap of logic to assume similar sized planets circling very different types of stars in an optimum orbital zone are "alien earths".
"In the new study, Dressing and her colleagues re-analyzed the red dwarfs in Kepler's field of view and found that nearly all are smaller and cooler than previously thought.
This new information bears strongly on the search for Earth-like alien planets, since roughly 75 percent of the galaxy's 100 billion or so stars are red dwarfs."
AAB Note: Red Dwarfs are about 2,000 to 5,000 degrees F cooler on their surface than our yellow sun, this would indicate that planets orbiting such a star in the zone that Venus, earth, and Mars circle our sun would on average be cooler, the inhabitable zone might be closer in than we presently think. We don't know what types of solar radiation planets orbiting Red Dwarfs receive compared to the out put of our own yellow sun.
" The researchers determined that 95 Kepler exoplanet candidates orbit red dwarfs. Using this information and their newly calculated stellar (and planetary) profiles, the team calculated that about 60 percent of red dwarfs likely host worlds smaller than Neptune.
Dressing and her colleagues then determined that Kepler has spotted three roughly Earth-size exoplanet candidates in the habitable zones of their parent red dwarfs.
One of these worlds is Kepler Object of Interest (KOI) 1422.02. This candidate's newly calculated size is 90 percent that of Earth, and it circles its star every 20 days. If the planet (and these characteristics) are confirmed, KOI 1422.02 may be the first "alien Earth" ever discovered."
AAB Note: We have no doubt that (KOI) 1422.02 is roughly earth sized, or orbits its star every 20 days in the speculative "best zone", but confirming those two facts don't prove an earth twin. How long is its day night cycle, does it have an atmosphere, what is the composition of the atmosphere, what is the average surface temperature? Is in a outer spiral of the galaxy or nearer the base of a spiral or the outer rim of the circular section?, Are there outer "guard planets", how violent in terms of cosmic collision objects is its neighborhood. Remember Earth shares the "life zone" with Venus and Mars but is nothing like those planets. Finding a pair or a few characteristics of a planet held in common with Earth is grounds to focus attention on studying that planet. It is a far cry from the actual discovery of an "alien earth".
NOW NEWS THAT DOES AFFECT OUR ESTIMATE:
Our speculation that there are far fewer real "earth like planets" in the galaxy than is estimated in typical journalistic coverage of the search for planets outside our solar system is based on two primary assumptions of fact. First our definition of "earth like" is different than what typical journalist and even some astronomers are using in their public announcements and journal articles. Basically they appear to mean near earth size, and in and orbit from their stars that is the equivalent of the width of the combined orbits of Venus, Earth, and Mars, or what some have called the "Goldilocks Zone". We define "earth like" as starting with the above size and position relative to the star being orbited, but include the elements that help regulate earth temperature ranges like rotation speed and seasonal axis of orbit change. We think that the description of earth like is really stretching things when scientist or journalist use this term for planets orbiting stars like red dwarfs and others not similar to our yellow sun. Finally we noted that our earth is protected from too frequent bombardment from space objects by both the presence of large outer "guard planets" and a moon, and that we are located not at the center of the galaxy but in a remote, small, unusually quiet in terms of meteors, comets, etc.spiral arm.
But now the estimated size of the "sweet spot" that our solar system is located in has to change. Astronomers using the VLBA (Very Long Baseline Array of the National Science Foundation) have found that the area of the galaxy that the earth is located in is actually a fairly prominent feature of the galaxy and much larger than previously estimated. The area where earth is located has been referred to as the "Local Arm", an apt name given the previously estimated relative position and size of our stellar immediate neighborhood. The "Local Arm" was thought to be a tiny spur two large radial strands known as the Sagittarius and Perseus Arms. The new VLBA measurements indicate a quite different status for our "little spur". Here is the new finding straight from the horse's mouth.
""Our new evidence suggests that the Local Arm should appear as a prominent feature of the Milky Way," Alberto Sanna, of the Max-Planck Institute for Radio Astronomy said in a statement. Sanna presented these findings at a news conference during the 222nd meeting of the American Astronomical Society.
In fact, the Local Arm looks to be as long as 16,000 light-years wide, Sanna said."
But as we noted previously the odds include a lot of variables such as atmospheric composition, solar orbit, axis rotation, changing axis inclination, moons and outer guard planets. The overwhelming odds are that the vast majority of planets in our "neighborhood" are similar in variety to the planets circling our sun, with the exception of earth. The numbers are too imprecise to offer estimates of the odds of finding a real earth like planet. But the the existence of at least one or more real earth like planets is definitely within the realm of possibility, and the estimate of the probability has to be adjusted somewhat upward from our original. The discovery that our "quiet neighborhood" is larger than we thought raises both the odds that earth like planets exist and the odds that they are in "our neighborhood". This would mean that any such may be within range of multi generational expedition ships capable of less than light speed. On the ocean men have set on voyages of years, especially during the European exploration of the world's ocean. The Polynesians set out on voyages of migration and discovery, knowing they had to leave behind whatever place they set from due to over crowding, or other factors the Polynesians pushed out into the ocean with ships laden with food crops, domestic animals, women and children, not knowing where they were going but not planning on coming back. Once new lands were discovered and settled the evolving navigational skills of the Polynesian communities allowed them to reestablish communications and trade. Ancestral homelands like Tahiti communicated with relatively new settlements like Hawaii. If we take a lesson from non western history, we can see that humans do sometimes set out on intentional multi- generational "voyages" or more properly "Sea Migrations".
The Polynesian sea migration was based on prior historical experience that the vast ocean was in fact dotted with islands. So the voyageurs were willing to shove off feeling the odds were in their favor of finding a new home. In a similar vein our probing of the cosmos for earth like planets may one day produce enough information to spark such a space voyage if we complete the research before anyone discovers the secret of faster than light propulsion. However we must keep in mind that biological research here on earth informs us that many forms of life exist in environments that we never imagined could support life here on earth such as the cold dark recesses of the bottom of the sea, at the mouth of subsea volcanic vents, in saline hot springs in local earth atmospheres devoid of light, over heated, or below freezing. And so we continue the cautionary message of our book PROTOCOLS. Space is an ocean, learn from our ocean history, don't repeat the worst errors of the "Columbian Exchange". Be prepared that "first contact" with alien life may be with deadly toxic microbes. Where are the Protocols for this event?
ARE WE ALONE?
The Milky way our home galaxy as it would appear if viewed from overhead
Side View of the Milky Way , Our Home Galaxy, We are located in one of the spiral arms on the outer edge.
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