Enceladus and Mimas: A Tale of Two Worlds
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Posted:Aug 24, 2019 7:26 pm
Last Updated:Apr 29, 2024 2:33 am
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Enceladus may be of the most unique and interesting places in the solar system. It is a small moon of Saturn, small enough that you could place it inside of the borders of the state of New Mexico. It has a diameter of about 310 miles. But it has unique characteristics that make it stand out, not just among the moons of Saturn, but even among all the moons of the solar system. The fact that it is unique in the Saturn system is the basis of today’s story.
The first thing tends notice about Enceladus is the relative lack of impact cratering. There are some, but large areas of the surface are free of evidence of impact events, indicting a young surface. The enormous surface cracks called “tiger stripes” are also very prominent. Perhaps the most striking feature of the small world is its surface albedo, the amount of light it reflects back into space. Enceladus has a surface albedo of nearly 100%. In other words, nearly all the light it receives from the sun is reflected back into space. All of these characteristics are related.
The albedo of Enceladus is due the fact that its surface is water ice. But even more interesting is what lies that crust of ice. At the core of Enceladus, there is likely a small core of rock, or at least silicate materials. Enceladus orbits Saturn at an average distance of 238,040 miles, roughly the distance as our moon is from the Earth (238,900 miles). But keep in mind that Saturn is ninety- times more massive than the Earth.
The orbital eccentricity of Enceladus, the degree which its orbit varies away from circular towards elliptical, is 0.0047. That is a pretty round orbit by solar system standards, but it still brings the little world a little over hundred miles closer Saturn at closest approach or the distance further at its most distant. This variance creates a huge amount of tidal friction, heating the solid core at the center of the little moon. As it orbits Saturn, it is constantly stretched and crushed, thus generating heat in the interior.
The interesting consequence of this enormous tidal heating is that between the surface crust of ice and the rocky interior, there appears be a global ocean of briny liquid water. In fact, even factoring in the small size of Enceladus, there may be as much water in the interior of this small moon as there is in all the oceans of Earth. It is the presence of this vast reservoir of liquid water that explains the lack of craters on the surface and those enormous cracks.
The tiger stripe cracks on the surface of Enceladus are the conduits for the Saturn system’s answer to Yellowstone Park. Through these enormous surface cracks, water from the interior constantly erupts toward the surface/ Some of this erupting water rains back upon Enceladus, constantly resurfacing the small world. The remainder escapes and constantly replenishes Saturn’s E-Ring.
The Cassini spacecraft flew through the water plumes of Enceladus on 2 occasions during its mission. The spacecraft was able to analyze the content of the plumes, which demonstrated conclusively that they are water, infused with various salts including Sodium Chloride (NaCl), Sodium Bicarbonate (NaHCo3) and traces of other salts. But more interesting was the finding that the plumes also contained about 1.5% methane as well as ammonia. Methane is a possible indication that something could be alive in the underground ocean of Enceladus.
Methane on Earth is almost entirely created by biological process. There are other chemical processes that can create methane, so those must be eliminated before the biology conclusion can be considered as primary. We will consider the implications of the presence of ammonia later.
When the Voyagers flew past Saturn in 1.9.8.0 and 1.9.8.1 respectively, we had tantalizing images of Enceladus that showed us the young surface, an indication of some yet mysterious recently active processes that were resurfacing the little moon. It wasn’t the Cassini mission that we were able determine that not was Enceladus geologically active in its recent history, it remains an active and dynamic world worthy of future exploration. But the dynamic nature of Enceladus opens the door to another mystery, closer in to Saturn itself.
Closer in to Saturn there is another small moon named Mimas. It has an equatorial diameter of about 8 miles, less than half the size of Enceladus but it has a similar composition and surface reflectivity at just over 96%. Mimas orbits Saturn at a distance of 1,289 miles, a little less than half orbital distance of Enceladus. It’s orbital eccentricity is substantially higher than that of Enceladus at 0.0196. Curiously, Mimas has a battered surface, the most striking surface feature being Herschel Crater, a huge impact scar 81 miles across that gives the moon an appearance which reminds many viewers of the Star Wars “Death Star.”
We live in a golden age of solar system exploration A generation ago, worlds like Enceladus and Mimas were points of light in the best telescopes we had on Earth. But the 2 Voyagers in the 80’s gave us the first glimpses of these worlds up close, then Cassini provided us the opportunity take an even closer and longer . of the greatest rewards of planetary astronomy in recent years has been the opportunity lift the veil on these worlds and pursuing the mysteries they present. It seems that nothing is ever quite what you expect when we have ventured into the solar system with our robotic emissaries, and every answer leads to dozens of new questions. Mimas and Enceladus present a case in point.
Here we have small worlds in orbit around Saturn. The closer in of the is frozen and battered. It has an ancient, cratered surface and is almost exactly the model we would expect for the icy, close in moons of Saturn. Yet just a small distance further , we have another small, icy world that is alive with cryovolcanism and just maybe, another opportunity find life in the solar system.
Mimas is closer in and has a significantly greater orbital eccentricity. Tidal friction in the interior makes it a much better candidate for dynamic geologic activity. Yet it is Enceladus, not Mimas, that is the dynamic, active world. Why?
Even after a decade and a half of exploration in the Saturn system, data from Cassini spacecraft hasn’t provided us with entirely satisfactory answers. We have some suspicions, based upon Cassini’s analysis of the geyser plumes of Enceladus. As we noted above, of the things Cassini found in the plumes was NH3, or as we it on Earth, ammonia. Most of us are familar with ammonia for its practical uses here on Earth, we use it for lots of household cleaning and it has an important role in helping transport us in our automobiles in cold weather months, as it goes by another called, “anti-freeze.” It may be possible that the presence of ammonia in the underground ocean of Enceladus is just sufficient keep the briny waters just enough remain liquid, while a dearth of ammonia on Mimas allowed the little moon freeze solid.
But I find this hypothesis unsatisfactory. It seems unlikely to that the availability of ammonia in the vicinity of Enceladus early in the body’s history would have been greater than for Mimas. So another possibility exists, that has been suggested by evidence from Cassini’s observations.
The interior of Mimas may not be frozen. It too, may contain an ocean of liquid water in its interior. This is suggested by observations of the moon’s orbital libration patterns, which suggests the possibility of a liquid interior. The fact that the impact event that created the Herschel Crater didn’t shatter the moon entirely also suggests that an interior ocean may have allowed the moon sufficient “give” at the surface at the time of collision to keep it intact. But then the question arises, why do we see the cryovolcanism on Enceladus, but not on Mimas?
At this point, we not run of answers, we get pretty short on reasonable conjecture. We still have a lot learn about our solar system, and the way gain answers is continue venture outward with our robotic explorers and perhaps, eventually, with humans as well. There are worse ways spend our and we do so with stunning regularity.
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TAMBORA: How a Massive Volcanic Eruption in the Early 19th Century Impacted Our World
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Posted:Aug 21, 2019 1:49 pm
Last Updated:Aug 24, 2019 7:14 pm
3371 Views
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Here is an old joke: What do Catherine the Great, Bozo the Clown and Winnie the Pooh have in common? If you don’t know this , you are about groan. They all have the middle . Now for a tougher . What do starving horses, the bicycle and Frankenstein’s monster have in common? Interestingly, the answer is the most powerful volcanic eruption in recorded human history.
Sumbawa Island is located on the eastern end of the Indonesian archipelago. In , the landscape of the island was dominated the thousand foot volcano known the locals as Tambora. The natives were unaware of the dangers the mountain presented. Geologists would later determine the volcanic mountain had been quiet for thousands of years, the most recent previous eruptions of the volcano probably occurred before humans reached the island. all changed on April 10, .
At about 8 PM local time day, the mountain exploded back life with the first of a series of violent eruptions. Ash was thrown 20 miles into the atmosphere, spreading around the entire planet. The island itself was covered with ash to a depth of 1.5 meters. Entire villages occupied thousands of residents were wiped almost instantly. Several other eruptions were follow, but all of them were little more than a cork pop in comparison the eruption would occur on April .
The most violent eruption took place on day. So much ash was erupted of the volcano the sun was not seen in Indonesia for several days after. The sound of the explosive event was reported over 500 miles away. Flaming magma bombarded the ocean, creating explosions of steam. A foot tsunami was created and the explosion of the volcano reduced its height from ,000 feet 9000. So much dust was thrown into the atmosphere spectacular sunsets could be seen nightly across the globe for most of the rest of the year. This set off dramatic alterations of the climate for nearly 3 years.
Snow fell in New England in the summer of 1.8.1.6 , over a year later, and was widely referred to as “the year without a summer” and “Eighteen hundred and froze to death” in both Europe and the Americas. More than 100,000 deaths were attributed to the direct and indirect effects of the eruption. In Indonesia alone, at least 40,000 were killed as the direct result of the eruption.
Naturally, the cold summers were accompanied widespread crop failures. In Germany, the oat crop failed almost completely in the summer of . Horses became so weak from the lack of oats for feed they had to be slaughtered. Without horses, transportation between villages became almost impossible. A German revolutionary the of Baron von Drais, later known simply as Karl Drais, began looking for a solution the transportation problem arose in the absence of sufficient numbers of capable horses.
Drais upon the idea of placing wheels in a on a frame, and balance could be achieved through dynamic steering. The vehicle he invented was narrow and could be ridden easily with a little practice. He called the device the Laufsmaschine. It became a popular device, and was nicknamed the dandy- or hobby-. A copy cat device called the velicopede was soon introduced in France.
The biggest issue was roads in most of Europe, particularly in the cities, were not particularly smooth and riding on them very far required considerable skill. overcome the hazards of using roads, people began riding the invention on sidewalks, causing rather severe danger other pedestrians. Numerous cities began banning the devices, including Milan, London, New York and Philadelphia. But , the atmospheric effects of the eruption of Tambora dissipated sufficiently crop failures had become less severe.
Drais’ Laufsmaschine didn’t disappear entirely though, and it was the direct ancestor of the modern bicycle. He was responsible for a of other interesting inventions, including the first typewriter with a keyboard and he made significant improvements on temporal wood stoves. But his radical political views brought him into disfavor with the ruling of the time. They attempted have him declared insane and locked up. effort failed, but they were able strip him of the pensions due from his inventions and he died a pauper in 51.
During the wet, cold summer of , a of British authors decided vacation in Switzerland. It was a included Lord Byron, Percy Shelley and a young Mary Shelley vacationed at a villa near Geneva, Switzerland. But the miserable weather forced them remain indoors for most of the stay.
The decided spend the miserable days indoors writing the most fearsome horror tales they could conceive. It was young Mary took the prize for the most terrifying with her work, “Frankenstein, or The Modern Prometheus.” Shelley’s gloomy and stormy settings throughout the novel stand as a testament to the conditions plagued Europe for 3 years after the eruption. Cold weather, crop failures, rainy summer days and massive flooding were common in Europe and North America. Shelley published her story in .
The massive eruption of a volcano on the other side of the planet had spawned a revolution in transportation, and an iconic monster. And now you know....the rest of the story.
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The Cardiff Giant: A Cautionary Tale in the Perils of Belief
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Posted:Aug 15, 2019 4:16 pm
Last Updated:Aug 15, 2019 4:21 pm
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Among the many gems of wisdom left to us by the late Dr. Carl Sagan, was the quip, "I have no interest in believing. I want to know." That is a pretty sound piece of wisdom we would all do well to follow more often, but it is not exactly a new problem in the realms of human experience. To relate our cautionary tale de jour, we set the Way Back Machine (some of you will get that one) to the year 1868, where we have an appointment to meet one George Hall.
By profession, Hall was a tobacconist, by belief an atheist: That was rather uncommon in the U.S. four years after the conclusion of the Civil War and not a whole lot more common 0 years later. We still have a lot of growing up to do as a species, and a nation. However, the genesis of our story begins with a Biblical argument Hall was having with a fundamentalist Methodist minister.
Hall took the position that while the Bible did contain some valuable moral lessons, the could not be taken literally. Like many who have actually taken time to read the Bible, he was unimpressed with its long list of inconsistencies, inaccuracies, preposterous stories and often ambigious moral teachings. The Reverend he was arguing with took the extreme opposite position, arguing that everything in the Bible had to be taken literally. As Hall pondered this conversation later, a little lightbulb must have appeared above his head. Or not, since they hadn't been invented just yet. That might have been another good story. Instead, one particular Biblical passage led Hall to author perhaps the most famous hoax of the 19th century, if not all time.
Genesis 6:4 reads, "There were giants in the Earth in those days" and Hall began to wonder if folks with beliefs similar to the good Reverend could be convinced that a large, stone statue that was excavated from the ground could be a real, petrified giant, as described early in the Old Testament. So he enlisted the aid of a few stone cutters and a farmer friend, Stub Newell of Cardiff, New York to put the question to the test. Using himself as a model, the stone cutters fashioned a foot stone "giant." The creation was then buried on Newell's farm, where it was later dug up by workers Newell hired to dig a new well on October , 1869 about a year after it was originally buried on the site.
The find became an immediate national sensation, and Hall ultimately profited wildly. People began streaming to Newell's farm to examine the wonder. Soon, Hall and Newell began charging visitors the rather excessive sum of 50 cents a piece to see it, yielding them a handsome return on Hall's original $2,600 investment to create the giant. Buoyed by proclamations of the authenticity of the giant by local religious leaders, its fame continued to spread like wildfire.
Soon Hall and Newell began taking the giant on tour and as Hall expected, it was proclaimed genuine in every city they visited. About the only note of dissent came from Dr. John F. Boynton, who suggested that it was carved by Jesuit missionaries in the th century to impress local natives. But most fervently believed it was an authentic, petrified giant, as described in the Bible.
Hall netted around $30,000 from touring the giant, then cashed in to the tune of $37,500 when it was purchased by a of businessmen in Syracuse who proposed to offer it a more permanent and prominent home for display. Hall was obviously laughing all the way to the bank as he accepted the offer and turned the giant over the the Syracuse . Soon after, the weight of scientific expertise came crashing down upon the Cardiff Giant.
The giant's arrival in Syracuse was followed quickly by Yale paleontologist Othniel C. Marsh of Bone Wars fame. Marsh quickly declared the giant to be not only a fake, but a rather obvious one. He noted the still visible chisel marks, indicating that the giant was definitely not a petrified creature, and the marks would have quickly worn away if the giant had been in the ground any length of time. It was clearly a fake.
Hall, who had already cashed in handsomely on his scheme saw no point in continuing the charade and came clean. By this point he was probably more than a little proud of having duped religious leaders all over the eastern United states with a clumsy hoax. One would have thought the matter would have quietly ended there, but the public didn't seem to care all that much that the giant was fake. They kept handing over their cash to come see it, many affectionately calling it Old Hoaxey.
Matters got even more of hand when the great showman of the era, Phineaus T. Barnum entered the picture. Never one to fail to see the opportunity to turn a profit, Barnum offered the Syracuse the astonishing sum of $60,000 for a 3 month lease of the giant. They should have accepted it and run. Instead, rather mysteriously, they declined Barnum's offer. Undeterred, Barnum hired an artist to create an exact plaster replica of the giant and displayed it in his museum in New York City. Barnum's fake of the fake brought in more than the original.
The Syracuse , probably kicking themselves in the rear end daily for having declined Barnum's original offer, decided to pursue the matter in a very typical American fashion: They launched a lawsuit against Barnum. But the judge assigned to the case was evidently weary of the foolishness the giant had unleased. He refused to hear the case unless the Syracuse could establish the authenticity of the original. They rather quickly dropped the lawsuit and the Cardiff Giant mania that had swept the nation finally quieted down.
Well, somewhat anyway. What is believed to be Barnum's fake continues to draw large crowds of curious visitors at Marvin's Marvelous Mechanical Museum near Detroit. The original spent a of years in a private home in Des Moines, Iowa, until the New York Historical Association managed to convince its owners to part with it for the sum of $30,000. It was placed on permanent display in the Farmer's Museum in Cooperstown, New York. It is rather clearly the town's second most popular tourist attraction, behind the Baseball Hall of Fame.
The moral of the story here should be clear: Not only is belief not enough, it can be downright dangerous. The desire to confirm a particular world view can easily be manipulated at the of truth and seperation of from its owners. It is easy enough to revile Hall and Newell for profiting handsomely for such a crude hoax. Yet I am able to enlist little sympathy for the masses who eagerly fell for it. Hall made precious little effort to make his hoax convincing. Quite the contrary, he did everything but chisel "This is a fake" into its chest. The more powerfully we want to believe in anything, the more fervently we have to question apparently supporting evidence, particularly when that evidence is highly questionable.
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The Dark Matter/Dark Energy Problem
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Posted:Aug 15, 2019 3:04 pm
Last Updated:Aug 24, 2019 7:04 pm
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The question of the existence of dark matter and dark energy represents the greatest challenge our understanding of the physics of modern cosmology. The present argument states that both have exist, or there is something seriously wrong with our present understanding of physics. I tend lean towards the latter suggestion, simply because the notion that something has to exist in order for the universe to make sense from our present perspective is not a scientific argument.
It smacks of the old religious claim that the existence of a watch automatically implies a watchmaker. Effectively, it becomes an argument from ignorance that may well be true, but science can not allow itself to accept arguments founded on faith. If dark matter does exist, it should be detectable.
The means of doing so are complex and would require explanations beyond the scope of this present piece. Perhaps I will tackle that at a later date. Suffice it to say that at least at present, numerous ingenius methods have been incorporated in the search, all have yielded extremely disappointing results.
There has never been any detection of the expected signals from dark matter above the expected background noise. In effect, the search for dark matter has been about as productive as the search for Sasquatch. the circumstances might expect a greater degree of skepticism, but the nonexistence of bigfoot doesn't threaten any modern, cherished principles in biology. However, dark matter does generate its share of critics. I am among them.
Some new and interesting proposals have been offered that do challenge some basic concepts of physics without rewriting the entire collection of physics texts . Gravity has always been regarded as one of the 4 fundamental forces of nature, by far the weakest, but exerting its influence over the greatest distance. But one new proposal suggests that we might need regard gravity in an entirely different way, and consider its relationship entropy. In effect, perhaps we need stop thinking of gravity as a fundamental force of nature.
Entropy stands as perhaps the most poorly understood concept of physics, a point to which I will briefly return later. But in order to clarify what is meant by entropy, let's explore what it is as briefly as possible. The description of entropy that is generally offered is an explanation of the laws of thermodynamics and, put very simply, entropy is the unusable part of any system, for instance, the waste heat generated by your computer. This is a decent description, but let's try a different .
Imagine a brand new deck of cards. You take them of the box and describe the order of the cards in the box. You could note that the 2 jokers are on top, followed by the all of the spades beginning with the Ace, then the King, Queen, Jack and the numbered cards in descending order from down 2. That suit is followed by the hearts, clubs and diamonds all in the order. That is all the information required describe the initial order of the cards in the deck.
Now, shuffle the deck a of times and the of information that will be required describe the order of the deck will be considerably greater. In effect, you may have list the position of every single in the deck. The act of shuffling the deck has added entropy the system, increasing its disorder. The more information it takes describe a system, the more entropy it has. Entropy is essentially the tendency of systems proceed from order disorder.
A recently published paper suggests that thermodynamics is related information through the holographic principle as a model for the universe. The information contained in a region of space depends on the arrangement of objects within that region and moving objects, which are effectively everything in the universe, change the entropy within the region. This creates an entropic force that acts exactly like gravity. From the basic idea of information entropy, all of Einstein's equations of general relativity can be precisely derived.
This is an elegant way resolve the problem of why gravity just doesn't fit very well into quantum physics. But it doesn't get us entirely of the woods with the problems that the suggestion of dark matter and energy seem to solve . For thing, since entropic gravity seems behave precisely like general relativity, there is no way experimentally distinguish the 2, thus it can not be established as a superior theory. There is also a problem with trying make the model work in a closed system of masses. The existence of entropic gravity works if you place some very bizarre constraints on the entropy within the system.
But there is at least an interesting suggestion that gravity, dark matter and dark energy might all be connected through entropy. additional problem has be addressed. This emergent gravity simply doesn't do a very good job of addressing large scale effects in the universe, such as the clustering of galaxies. Dark matter and dark energy address that phenomenon quite elegantly, but the question would be so much easier if they would do us the favor of allowing themselves be detected.
Still, the notion that thermodynamics and gravity are connected at a deep level is exciting, and something cosmologists are likely be addressing energetically in the coming years.
Now, let's step back for just a moment and briefly discuss the most misused principle of science in lay discussions, the second law of thermodynamics. Deniers of evolution frequently cite the second law as proof that evolution can not occur. The second law basically states that in a closed system, order will proceed toward disorder. Since the evolution of life from simple to complex represents a trend towards greater order, evolution must be a violation of the second law, in their view. This argument fails spectacularly on 2 levels.
First, they ignore an important aspect of what the second law states: That we must be describing a closed system. Life on Earth is, by no means, a closed system. The true closed system we know anything about is the universe itself and I frequently question whether or not our universe is a truly closed system. The Earth receives input daily, hourly and by the second and microsecond from many other sources, most importantly, the sun. While the second law does note that systems tend proceed from order disorder, there is nothing in the second law that states that subsystems within a greater system can not become more orderly, providing that the overall system is proceeding towards disorder.
Let’s return for a moment, to the example of shuffling our deck of cards. Starting from a precise order, every shuffle increases the overall disorder, or entropy of the deck as a closed system. HOWEVER, it is entirely possible that each successive shuffle may be increasing the order in specific parts of the deck. Further, the fact that the shuffler is expending energy shuffle the deck is part of the overall system. The deck itself is not a closed system.
In our case, might argue that life on Earth represents a trend towards order, but the Earth-sun system is constantly increasing in disorder, since entropy within the sun is increasing much faster than order is being created on Earth. Second, the argument that evolution is a move away from disorder may not be a well defined claim. Since the present structure of the Earth's biosphere is considerably more complex than it was at a time when it was dominated by single cell organisms, it can easily be noted that the entropy of the system has increased significantly since it takes more information to describe the system. On either or both counts, the critics of evolution fail to understand the science they are mistakenly attempting to use to justify a bad argument.
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Pondering the Measure of a Year: Why do we celebrate the New Year on January 1?
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Posted:Jul 21, 2019 6:24 am
Last Updated:Aug 24, 2019 6:53 pm
2968 Views
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A question I get quite often when I am speaking of subjects astronomical is, why do we celebrate the New Year on January 1? Is there any particular significance particular date that lends itself starting our year then, or is the matter arbitrary? There is a simple answer these questions, and then there are several complicated answers. I can start simply answering the question in the simple way and stating, No, there is no astronomical significance our celebration of the New Year on January 1, and yes, it is sort of arbitrary. But I have never been stop at answering questions in a simple way when I get the opportunity to delve into more complex discussions.
So let’s start with a somewhat more basic question. Just what is a year? Ask this question to most people and you will generally get a puzzled as if they are pondering just what sort of trap you are setting for them, then they will indignantly answer, a year is the time it takes for the Earth complete an orbit around the sun. Of course, that is the right answer. Well, it is sort of the right answer anyway. It is also a very wrong answer in an important way, because the reality is, from a human perspective, it isn’t the way we measure a year. For most of our history on the planet, the time it took for the Earth to complete an orbit around the sun hasn’t been a terribly important piece of information to our survival as a species. But let’s consider answer for a moment.
If you want to measure the time it takes for the Earth to complete an orbit around the sun, how do you do it reliably? The best clock we have is the stars. So, let’s say there is a particularly bright star which, at some point during the year, appears directly at zenith, or in other words, directly overhead. It would then be a relatively straightforward matter to construct a small structure with a very small hole at the top. When bright star is directly overhead, it will then, and then, shine directly into the very small hole in your structure. So you just keep track of the star during the course of the year and when it once again shines through the little hole in your structure, you know the Earth has completed an orbit of the sun with respect to the stars. In other words a year has passed. But that isn’t how we humans measure a year because, as I noted above, it isn’t important us. The time it takes for the Earth complete an orbit of the sun with respect the stars is called the sidereal year.
Through most of human history, it has been important for us to keep track of the Earth’s seasonal cycle. When we were primarily hunter-gatherers, animal migration patterns and times when various plants produced fruit or other edibles are tied to the seasonal cycle. When we invented agriculture, it became critical for us to track the seasons so we knew when to plant crops. In earlier times, keeping track of the north and south movements of the sun became a reliable way to track the seasons, so humans a lot of attention apparent solar movements. Of course, it wasn’t the sun that was moving, but Earth’s approximately 23 degree axial tilt and the fact the north pole always points in essentially the direction provides the illusion it is. So the earliest human calendars typically charted a year that began with the Vernal Equinox, the day when the sun crosses the celestial equator moving north. It was the first day of spring, and the time when the weather would generally cooperate with planting the new year’s crops.
Our modern calendars still reflect the bias of a year which began with the Vernal Equinox in March. The month of September literally means 7th month, even though in modern times, it is the . Similarly, October means 8th month, November means month and December, 10th month. March was, of course, the first month of the new year. The months of January and February were typically so economically unimportant many ancient civilizations didn’t give them names. Some of the summer months originally had names reflected a numerical progression, but they were eventually appropriated politicians renamed them promote their own immortality.
The point here is ancient civilizations didn’t care much how long it too for the Earth to orbit the sun, nor did they care much it did. The question of whether the Earth orbited the Sun or the Sun orbited the Earth led some intense theological debates a few centuries ago, but our ancestors, the question was more or less irrelevant. What they were concerned about was the length of time from Vernal Equinox to Vernal Equinox. And right now most of you are probably asking, isn’t time a year? The answer is, yes, But it isn’t the as the sidereal year.
As Earth rotates on its axis and revolves around the sun in its orbit, there are important forces acting upon it; the gravitation pull of the moon and the gravitational pull of the sun. These gravitational forces cause the Earth wobble as it spins on its axis, much as a top wobbles as you watch it spin in a table. This wobble causes the Earth to complete its seasonal cycle about 20 minutes faster than it takes for the Earth to complete an orbit around the sun with respect to the stars. Thus, the time it takes for the Earth to complete its seasonal cycle is called the tropical year. The sidereal year is 365 days, 6 hours 9 minutes and 9.76 seconds. The Tropical year is 365 days, 5 hours, 48 minutes and 45 seconds. There are other ways to measure the year as well, for example the anomalistic year, which is the time it takes for the Earth to complete a revolution around the sun with respect to the apsides. This is a rather important consideration in astronomical calculations, but not important to our discussion here.
The difference between the time it takes for the Earth to complete its seasonal cycle, the tropical year and the time it takes to complete an orbit of the sun with respect to the stars, the sidereal year has some interesting consequences. Our human measure of a year is, for obvious important economic considerations, based on the tropical year. Back when we began the year with the Vernal Equinox, not was the sun crossing the celestial equator, it was also entering the constellation Aries, the ram. That is why Aries is listed as the first constellation of the zodiac. But the difference in the tropical and sidereal years causes an eastward shift of the stars annually. Over the course of a year or even a decade, this shift isn’t terribly important. Over the course of centuries it becomes huge. Since the time the zodiac was first mapped, the sun has dropped a full constellation behind. It won’t cycle back to the point where it enters the constellation of Aries on the date of the Vernal Equinox for about another 23,000 years. This demonstrates why we can’t rely on the sidereal year for agricultural purposes.
So, why do we start the year on January 1, when there is obviously an elegant and pretty rational reason to start with with a date which has astronomical and agricultural significance? Wouldn’t it make more sense to start it on the Vernal or Autumnal Equinox, or even the Summer or Winter Solstice? Well, yes, it would. But now we enter the realm of politics, which rarely has a rational basis.
Prior to 45 B.C., the calendars most commonly were based on lunar rather than solar cycles. These were messy and complicated and almost nobody was able keep accurate track of the year. So Julius Caesar enlisted the of an Alexandrian astronomer, Sosigenes, do away with the lunar calendar and implement a more accurate solar calendar. In order reconcile the change as seamlessly as possible, Caesar added 67 days 46 B.C. which caused 45 B.C. begin on January 1. Caesar’s calendar was based on a 365 day year, with 1 day added the month of February every 4th year reconcile the fact Sosigenes calculated the year be 365.25 days long.
All was hunky dory 1.5.7.0, when the Julian calendar had fallen 10 days of sync with the observed seasonal cycle due the fact Sosigenes calculation of the length of the year was a little off. So Pope Gregory XIII commissioned the astronomer Christopher Clavius to construct a more accurate calendar. Clavius new Gregorian made the correction which 1 of every 4 centennial years would be a leap year, cleaning up the error of the Julian calendar. It also became necessary delete 10 days from the year 1.5. 8.2, which caused serious discontent among the peasants believed their lives had been shortened 10 days by Papal edict.
Not everyone adopted the Gregorian calendar right away. Great Britain and the colonies didn’t adopt it 1.7.5.2, which created some interesting problems for us later on. By the time England and what is now the U.S. adopted the calendar it was now days of sync with the seasonal cycle. Once again, there was discontent among some less educated folk regarding the loss of days of their life. Further, the change messed up a holiday we now celebrate. According the old Julian calendar, which was still in effect the time of Washington’s birth, George was born on February ,1.7. 3.1. But after the change, which deleted days from the old Julian calendar, advanced the year by 1 year, and moved the date of the new year January 1 instead of March 25, we now recognize his birth date as February 22, 1.7.3.2.
But the calendar is now in reasonably good accord with the tropical year, the New Year is celebrated on January 1 and all is right with world...well almost. But next time you are in a museum or planetarium and some smart ass astronomer asks you tell him or her what a year is, I recommend this response: “Well, most people would tell you it is the time it takes for the Earth orbit the sun, but in reality, what we the year is the time it takes for the Earth complete its seasonal cycle.” I guarantee you will get a sly wink from the astronomer and a puzzled from the others gathered.
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Lunar Lunacy: Why People Believe That the Full Moon Influences Human Behavior
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Posted:Jul 21, 2019 6:10 am
Last Updated:Aug 25, 2019 5:47 am
2860 Views
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A comparatively rare, but widely reported astronomical non-event has prompted the usual flooding of boxes as is typical when such happenings occur, along with some inevitable debates about nonsense. The event in question is the Super Blue Blood moon of January 31, 2.0.1.8. Blue moons are simply the second full moon of any calendar month and they happen about once every and a half years, so they aren't terribly rare.
Blood moons are simply full lunar eclipses as they appear due the reddish color cast Earth's shadow. I have recently seen a definition of the blood moon as being the 4th consecutive full lunar eclipse with no partials interrupting the chain. This is internet nonsense. I am not sure came up with this particular definition, but it is not in professional or amateur circles. Lunar eclipses occur at least twice, and as many as times annually, so they are not terribly unusual either and have little astronomical value or significance.
The Super moon has become a bit of a popular press rage over the past year or so. Like every other object in the solar system, our moon has an elliptical orbit, bringing it closer than its average distance of 238,900 miles at times and further at others. The moon can be as close as 221,524 miles and as distant as 252,688 miles. When it is near perigee, the popular press takes great joy in reporting a "super moon."
Super moon's aren't all super. The moon portends about 0.5 degrees of arc on average and it can appear up about percent larger at its very closest approaches. But for an object which appears about the size of a quarter held at arm's length, a percent variation is pretty hard see. The difference in brightness isn't significant either.
A super moon can increase in brightness about -0.5 magnitude, but the moon already has an apparent magnitude of negative point .So this variation in magnitude is also not very significant unless you are an exceptionally keen observer.
This rather long-winded introduction the main discussion is just a verbose way of saying the Super Blue Blood moon is just another lunar eclipse. The combination of the , while rare, doesn't make the event any more or less spectacular, if you enjoy watching lunar eclipses. Personally, I rarely bother with them these days. I have seen enough of them they are not particularly interesting and the scientific value is nil.
But the moon holds a special place in our folklore and contemporary beliefs. Werewolves carried about their horrifying antics during the light of the full moon, and many cultures had similar tales of terrifying creatures carrying out their misdeeds during this lunar phase. The belief persists into modern times somehow the full moon affects our behavior.
This belief is ancient and even our modern word "lunacy" is derived from the persistent belief somehow, the moon plays a role in human misbehavior. Others hold the moon also plays a role in increased of childbirth.
It is frequently reported law enforcement officers, personnel in emergency rooms, and maternity wards swear without compromise the full moon brings about busy nights in their respective lives. The claim would be interesting if true, but repeated, well structured scientific studies into this question reveal there is no evident statistical correlation between the full moon and increases in crime , animal attacks, childbirth or much of anything else which is frequently suggested. Permit me to cite a few of many studies dispute the popular claims.
The largest study ever conducted on the possible link between lunar phases and childbirth, of many, was published in 2001. It was conducted the astronomer and physicist Daniel Caton examined 20 years of data from the National Center for Health Statistics — about 70 million U.S. births. He found no correlation between the full moon and deliveries. At about the time, French researchers looked at .5 million births in Europe and also discovered no patterns.
A 2.0.1.5. study the National Institute of Health and the U.S. National Library of Medicine concluded no correlation could be found between the full moon and childbirth or hospital admissions. summarize the results of some of the most recent studies:
*In 10 studies on the relationship between the full Moon and crime , violence, and aggression, 8 showed no correlation.
*In studies on the correlation of the full Moon and suicide , all showed no correlation.
*In studies on the full moon and health effects, showed no correlation, showed a correlation events days after a full moon, and showed while unintentional poisoning was up, intentional poisoning was down.
*In 7 studies of the lunar cycle and automobile accidents, all 7 showed no correlation.
*It has been shown predatory attacks lions upon humans are less likely to happen when a moon is above the horizon. Because a full moon is above the horizon practically all night, humans ( have very poor vision at night) are more likely scare off a lion.
I have learned in the course of a of discussions on this topic no of well controlled scientific studies are likely to convince the believers. This isn't uncommon. When people adopt a belief, they are reluctant to release it, regardless of how much contrary evidence can be offered. So the question becomes reasonable: Just why are people so inclined to believe the full moon affects our behavior?
I think there are a of factors at work here. The influence of folklore and deep cultural conditioning can't be ignored. But there are other factors at here which will tend reinforce the inclinations toward believing in the lunar effect, even when it doesn't exist. It is apparent the kinds of incidents which can promote these beliefs are particularly strong for those work in environments typical large, busy hospitals or other stress occupations like law enforcement officers.
Over a period of time, statistics can easily be collected for the typical numbers of emergency room visits or maternity ward admissions per day. The longer the data base is collected, the more accurate the averages can be. Long time workers in those facilities very likely have access data and probably even develop a sense for the averages even in the absence of published data.
However from a purely mathematical perspective, the most unusual day workers in this type of environment will experience is a statistically "average" day. Almost every single day they work, they are likely experience either above or average patient traffic. With this simple fact in mind, every single time a full moon occurs, there is essentially a 50-50 chance above average activity will be experienced.
Confirmation bias comes into with this simple reality. If a particular night brings unusually patient traffic and the bias toward belief in a lunar effect is already present, a will reinforce the preexisting bias. On the other hand, full moon nights with average activity are likely be forgotten. Further, I suspect in this type of environment, even nights with average statistical traffic can seem unusually busy if the cases are particularly challenging. This, again, would reinforce the bias.
There is also a rather simple issue of blind reinforcement. It might be a particularly busy and trying evening in the emergency room, someone offers, "There must be a full moon tonight!" Heads shake in agreement, but no one bothers check and the evening goes as a "" without confirmation.
The moon itself is technically full night during its phase cycle, but the casual observer, it appears full at least night before and night after the actual full phase. If a busy night occurs on of these nights, it is again likely be recorded as evidence for the pattern, even though the moon is not truly full. Statistically speaking, there is a 1 in 8 chance at least of the evenings won't produce above average activity.
Correlation is not necessarily causation. Events related in time are not always related each other. An unusually busy night in the maternity ward or emergency room, a particularly trying night for law enforcement, or an evening with an unusually sizable of animal bites being reported around a city can just as easily occur on the night of a full moon as any other night. But when a bias already exists favoring a belief the lunar phase is driving activity, the belief grows stronger. But for those hold this belief, it becomes incumbent demonstrate the factual nature of the belief explaining the path of cause.
In reality, the moon is always in a "full" phase. Half of it is always lit the sun. We don't see it way from Earth, but from the perspective of the sun and the moon itself, there is no particular difference between what we see as the full moon and the moon in a quarter phase. The moon is tidally locked with respect the Earth, so the is always presented us. At certain times, is fully illuminated the sun. At other times, partially and in its new phase, it is completely shrouded in darkness and not visible us at all. But if there were some force which had a true influence on human behavior, this force would be acting upon us all the time regardless of the specific temporal phase.
This possibility which can't be entirely excluded is a modest psychological effect, which could for slight occasional variations showing up marginally in crime reports. If a person might be inclined do evil, and holds a lunar effect bias might use it as a justifying excuse for his or her behavior. But even this influence is demonstrably so tiny as be statistically insignificant given the overwhelming lack of data correlated in the studies. Anecdotal evidence on this question is common, but without value for many of the reasons discussed above.
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Time and Relativity: Is the Creator Hypothesis Necessary?
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Posted:Jul 21, 2019 5:47 am
Last Updated:Aug 24, 2019 2:15 pm
2322 Views
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Concepts of Einstein’s theories of relativity create confounding, counter-intuitive concepts with which people struggle when attempting some level of understanding. I think the one question I get more often than any other when the subject of relativity comes up involves the question of adding velocities. Suppose you are in a spaceship traveling very near the speed of light: Let’s say for the sake of argument, you are traveling at only 100 mph less than light speed . You grow angry at one of your shipmates, and fire a pistol at him as he is standing near the front of the ship. Wouldn’t the bullet have to be traveling faster than light after it is fired? After all, if you fire a pistol out of a moving car, the bullet benefits from the forward momentum of the car.
Similarly, when we launch planetary probes, we launch them from Florida in an easterly direction to take advantage of the Earth’s approximate rotational velocity of 1000 mph. Wouldn’t the bullet aboard the spaceship do the same, if fired in the direction of motion? Doesn’t violate a fundamental premise of relativity, nothing can faster than light?
The answer is, no, for 2 basic reasons. First, we note an issue doesn’t really answer the question, but is worth discussing. Nothing in Einstein’s theories of relativity suggest that traveling faster than light isn’t possible. What Einstein told us is, no massive object can move AT the speed of light. As a massive object accelerates, a certain portion of the energy that is going into accelerating the object is increasing its mass. The closer you get to light speed, the more massive the object becomes. By the time you reach the speed of light, the object would become infinitely massive and infinite energy would be required to continue to propel infinite mass. Since both infinite mass and infinite energy can’t exist in the same place and time in the same universe, you can’t travel at the speed of light. In order to travel faster than light, you would have to accelerate through the speed of light at some point. So while Einstein didn’t specifically prohibit faster than light travel , it is a bit difficult to figure out how you could pull it off.
Second, and more to the point, we come to the entire matter of frames of reference. If you are inside the spaceship, you more or less perceive yourself as standing still as space races past you at very near light speed. You fire your bullet and it travels the distance between you and your unfortunate victim at the typical speed of a bullet. In other words, everything on the spaceship appears to happen exactly the same as it would if you committed your horrifying act of homicide on the Earth.
But suppose a stationary observer outside of the spaceship could watch the same incident occur. How would an outside witness see the events unfold? Well, things would look a lot different. First of all, a spaceship traveling close to the speed of light would be foreshortened in the direction of motion. So the outside observer would see you and your victim standing much closer together, so the bullet has a considerably shorter distance to traverse. Further, for the occupants inside the spaceship, time is traveling slower from the perspective of the outside observer because the spaceship traveling near the speed of light is vastly more massive. So everything inside appears to be happening in slow motion.
The consequence of the foreshortening and slower moving time means that the bullet is still traveling well below the speed of light for all observers and relativity is not violated. The matter of the relative nature of the passage of time is the principle one I wish to address in this context, because it has profound implications, ultimately for how we should view the creation of the universe.
As you sit in your living room, or wherever you may be reading this piece and believe me, is a matter upon which I have no real interest in speculating deeply, time is passing at a familiar rate . The seconds tick away as they always have. The passage of 60 of them define a minute. When 60 of those minutes pass , we note the passage of an hour. A day is defined 24 of those hours and so on. When we are doing something we enjoy, time can seem to fly by rapidly. but by contrast, tedious tasks almost seem to slow the passage of time. Einstein once quipped sitting on a hot stove for a second can seem like an hour, while an hour in the company of a beautiful woman can seem to pass in minutes. , that he explained, is relativity.
But the passage of time really is relative. If you have an acquaintance aboard the International Space Station, time is actually passing slightly more rapidly for them while they are living aboard the station than it is for you over the same period. This is because you are closer to the center of the Earth, in other words, closer to a point source of gravity. The astronauts aboard I.S.S. are in micro-gravity, thus their clocks are moving more rapidly. This is not a theoretical concept. Not only is it true and measurable, it has significant effects on your everyday life which you may have never considered.
Most of you probably have a smartphone with a G.P.S. application, or perhaps some sort of G.P.S. device in your automobile. G.P.S. stands for Global Positioning System. Currently, there are 24 satellites in Earth orbit that constitute the system. They orbit the Earth at an altitude of about ,twelve thousand miles up, about half way to geostationary orbit. In other words, they don’t stay in the same place with respect to the ground below, but all of them maintain their relative positions with respect to each other.
Wherever you are on the Earth at any given time, there are always 8 satellites somewhere above your present horizon. It takes 4 of these satellites to determine your present position on the planet, and they can locate you to within about 9 inches. Your GPS receiver seeks out the nearest satellite. It basically defines your position on the surface of the Earth by timing the signal from your receiver, and offers that your present position is a point somewhere on a very large circle which can be drawn out as if the satellite is the top of a compass and the distance to you is the point of the pencil. Then your receiver contacts the second closest satellite, which also communicates with the first one. The 2 satellites now have determined you are at one of 2 points along the original circle.
Your receiver then contacts the third satellite, which eliminates one of those 2 points, pinpointing your current position on the surface of the Earth. However, you may not be on the surface of the Earth, or at least not at sea level. Therefore, the 4th satellite determines your altitude above sea level. In this way, your precise position is determined. The 4 satellites also cross check each other. This is necessary because you may be moving, and it also eliminates error, which is critical. All of these communications are happening at the speed of light. An error of a thousandth of a second by any one of the satellites would result in a one hundred eighty six mile error by the system. So it is a constant system of measurement and verification.
Our GPS satellites have the most precise atomic clocks we are able to build. But they are in orbit and as we have established, clocks in orbit move more rapidly than clocks on the ground. Therefore, the satellites must constantly remain in communications with equally accurate Earth based clocks for constant re-calibration. If these updates were not done, the effects of relativistic time dilation would throw off the information provided GPS satellites about 6 miles day. If you are on a navy ship launching a cruise missile at an enemy target, a 6 mile miss is obviously a rather unacceptable and potentially disastrous outcome.
So, we have established the time dilation aspects of relativity are measurable fact. Let’s consider now, the extreme case; black holes. But first, we will explore the ultimate fate of our sun. Our sun shines by virtue of the process of hydrogen fusion. Hydrogen atoms fuse together into helium atoms. This process releases energy partially in the form of photons and heat. The existence of the sun, or any star is a long term battle between expansion from internally generated heat and collapse from the enormous mass which generates gravity. The heat energy from fusion counterbalances the inward, collapsing pressure of gravity. Helium is heavier than hydrogen and sinks toward the center. Helium atoms fuse into heavier elements like neon, oxygen and carbon. Further fusion occurs until iron atoms are fused, which collect in the center of the sun. The process of iron fusion produces no energy.
Some 5 billion years from now, the sun will have exhausted most of its hydrogen and helium and the core will contain a huge amount of iron. Gravity will begin to win the 10 billion year old battle with internal heat, no longer generated in sufficient amounts by the largely iron core, and the sun will begin to collapse. But this will bring the remaining hydrogen atoms (and other atoms lighter than iron) into close proximity and furious fusion reactions will resume. Heat launches its counterattack causing the sun to bloat up into a gigantic red giant star. Mercury, Venus and perhaps the Earth will be consumed this enormous giant. But it is the last stand for heat energy. Almost all of the remaining hydrogen and helium will comparatively quickly fuse into heavier elements. The collapse will begin once again. For a star the size of the sun, the collapse will continue until electrons come into close proximity, permitting the weak nuclear force to overcome the collapse. (This is something of an oversimplification to avoid a rather complex discussion of physics. The actual process of halting the collapse is electron degeneracy pressure.) The result is a dense, white dwarf star. A teaspoon of material from this white dwarf would weigh in the neighborhood of fifteen tons.
For a star a few times more massive than the sun, the process causes the sun to bloat into a red giant is replaced by an enormous explosion called a supernova, which releases a large part of its mass and importantly, heavy atoms like oxygen and carbon and even heavier atoms into space. But once the collapse of the remaining mass begins, the weak nuclear force can not halt the collapse. Now, elementary particles are squashed out of existence. Only a sort of crushed neutron soup can halt the star’s collapse and it is saved by the strong nuclear force. (Again, I am simplifying here to sidestep a detailed explanation of neutron degeneracy pressure.) We are left with a neutron star, a body so dense a teaspoon of material would weigh 10 million tons. A star once a few times larger than our sun is now compressed into a sphere perhaps miles across and spinning at a rate of hundreds of times second.
But a star 10 or times or more massive than our sun can’t be saved the strong nuclear force. There is no force in nature capable of halting this collapse. All of the star’s previous mass is effectively crushed out of existence, as least as we define it the laws of physics we understand. All is left behind is a tiny singularity; all the gravity of the star with no mass.
The laws of physics in our universe no longer operate beyond the event horizon of a black hole. Beyond the event horizon, the black hole’s gravity is so intense even light cannot escape. It is bent back towards the singularity. Suppose we could into one, and escape the obvious problems of entering into a gravitational field this profound. Gravitational attraction declines as the inverse square of the distance. At some point inside of a black hole, your feet would be attracted enormously more powerfully than your head, stretching your body to an extreme in a process some physicists jokingly call spaghetification. But let’s ignore problem for a moment and consider the nature of time in a black hole.
We have already noted time slows as you near a point source of gravity. Black holes would be the most powerful gravitational point sources we can imagine. Consequently, the closer you get to the center of a black hole, the slower time would move. If you get close enough to singularity, time would stop, altogether. In effect, you could never reach the singularity of black hole. Of course, a few thousand other things would cause your demise a long time before you got close to the singularity, but rather than consider myriad of misfortunes, let’s leave our black hole and return home, to the present where in space and the present when in time.
But we are going to embark on another adventure now. We are assigning ourselves god-like powers for a few moments, giving ourselves the privilege of reversing the flow of time in the universe. We are going to turn expansion into contraction and permit effect to precede cause in time. We are going to go back to the beginning, to the moment of “creation” itself.
We watch as our sun and solar system disintegrate into a cloud of atoms and molecules. The hydrogen and helium that comprise our sun and the heavier elements that constitute the planets collapse back into an earlier star. The galaxies draw back together. Heavy elements return to the huge stars which created them. Eventually all the stars wink out and the universe disperses into hydrogen and helium atoms only, then those dissolve into smaller elementary particles and eventually quarks. As the universe shrinks, it grows enormously hotter. Eventually, the collapse completes as all the energy and mass in our present universe becomes a singularity, about the size of a single proton. Our entire universe is now a tiny black hole. We have returned to the moment of the big bang.
As a black hole, our laws of physics no longer exist. In the singularity which is now the universe, there is no time. Time can not exist this close to a singularity. There is no moment “before the big bang” because, time now does not exist.
So did a creator cause the big bang? The question becomes meaningless, as does a creator. There is no time for a creator to create. There is no space for a creator to create in, or exist in. With all due respect to those of faith, everything necessary for our universe now exists in a singularity and there is no “before” to question. As Stephen Hawking once so eloquently remarked, there is nothing south of the South Pole. We have reached the point where our western philosophical concepts of beginnings and endings become entirely without meaning.
So, how did this singularity come into existence? We know that in the realms of the quantum universe, something is created from nothing all the time. Again, this is not a theoretical concept We have watched it happen. But it is a much more difficult subject, perhaps one to explore another time. For now, I simply leave you with the suggestion we have gone as far as questions are relevant.
Copyright twenty eighteen. All Rights Reserved
Dedicated to the loving memory of the late Professor Stephen Hawking.
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Censorship and the Suppression of Knowledge: Science as a Gateway to Truth and Understanding
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Posted:Jul 21, 2019 5:40 am
Last Updated:Aug 24, 2019 1:53 pm
2131 Views
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Facebook has a cookie system which frequently places posts on one's page which are related to topics which come up frequently in your posts. They may not be sites which you "like," but it is a means to introduce you to pages that might be of interest and of which you are not necessarily aware. Since I frequently offer posts on topics involving science, it came as no real surprise the other day when an article appeared on my page from a site calls itself "Christian Prophesy." The article was entitled "Scientific Evidence For the Existence of God." After skimming through the article, it was not particularly surprising that not only was there a complete absence of anything remotely resembling scientific proof of the existence of any deity, but it was also abundantly clear that the author of the article in question had no scientific training or real understanding of what constitutes scientific proof of anything.
In the discussion area following the article, someone rather quickly called the authors of the article to task over the complete lack of the evidence implied in the title and very correctly asked directly if the authors really understood what qualifies as solid scientific evidence. In a rather long winded response someone posting under the name of the site, the question was not only avoided, but the author rambled on about completely unrelated topics. Inevitably, the response included an attack on evolution and the ridiculous claim there is no scientific proof of evolution. The author then quickly offered a challenge to anyone to cite any real proof evolution is factual, and has ever occurred.
Challenges of nature are naturally irresistable to me and I offered in response that evolution has been witnessed in the field and under controlled conditions in the laboratory, and I included 5 key points strongly supporting the theory of evolution, as well as the offer to provide dozens more if the author did not accept those 5. The points I offered were as follows:
1. All cells on Earth, from our white blood cells, to simple bacteria, to cells in the leaves of trees, are capable of reading any piece of DNA from any life form on Earth. It doesn't matter if you are an oak tree, a jellyfish or a human. Your DNA can recognize and read the DNA from any other life form. This is very strong evidence for a common ancestor from which all life descended. It would clearly make more sense for an "intelligent designer" to make DNA specific to individual life forms, which would eliminate a lot of genetic disorders and genetic proof-reading errors. But that is not how life is constituted.
2. The fossil record shows the simplest fossils will be found in the oldest rocks, and it can also show a smooth and gradual transition from one form of life to another. You never find fossil evidence of stegosaurs in the same strata as kangaroos, for example. There are also numerous, unambiguous examples of the transitional forms radical Christians claim are not present. As a couple of examples, the transitional fossils demonstrating the evolution of whales from cow-like land mammals and of horses from small sized mammals is abundantly clear. However, it should be noted that all fossils are, by definition, transitional.
3. Human beings have approximately 98% of genes in common with chimpanzees and slightly less with gorillas, about 90% of genes in common with cats, 80% with cows, 75% with mice, and so on. This does not prove or even suggest we evolved from chimpanzees or cats, though, only we shared a common ancestor in the past. And the of difference between our genomes corresponds to how long ago our genetic lines diverged. Again, this makes no sense in a world where all life forms are created as independent entities, but it is perfectly clear when you view the world from the perspective that all life is intimately connected the common process of evolution.
4. Humans, , snakes, fish, monkeys, eels (and many more life forms) are all considered "chordates" because we belong to the phylum Chordata. One of the features of this phylum is , as embryos, all these life forms have gill slits, tails, and specific anatomical structures involving the spine. For humans (and other non-fish) the gill slits reform into the bones of the ear and jaw at a later stage in development. But, initially, all chordate embryos strongly resemble each other.
In fact, pig embryos are often dissected in biology classes because of how similar they look to human embryos. These common characteristics could only be possible if all members of the phylum Chordata descended from a common ancestor.
5. Bacteria colonies can only build up a resistance to antibiotics through evolution. It is important to note in every colony of bacteria, there are a tiny few individuals which are naturally resistant to certain antibiotics. This is because of the random nature of mutations.
When an antibiotic is applied, the initial innoculation will kill most bacteria, leaving behind only those few cells which happen to have the mutations necessary to resist the antibiotics. In subsequent generations, the resistant bacteria reproduce, forming a new colony where every member is resistant to the antibiotic. This is natural selection in action. The antibiotic is "selecting" for organisms which are resistant, and killing any are not.
The authors of this website did not attempt to respond with any sort of point point objection to these lines of evidence. It would have been difficult to do admittedly, particularly in light of the fact I had already forewarned them that I was standing with a host of other points of evidence. There was a response of sorts. They rather quickly deleted my post and prevented me from further commenting on the thread. That isn't terribly surprising. Suppression of knowledge is not at all uncommon in human disciplines like politics and religion. In science, it is anathema. Reasonable ideas are pursued as long as they are supported reasonable evidence. But not all ideas are created equal. As the late Dr. Carl Sagan once noted, you don't get to wear the martyred cloak of Galileo simply having ideas run counter to the conventional wisdom. You also have to be right.
Admittedly, I was somewhat disappointed I didn't get the opportunity to drag out the heavy artillery. The human body, marvelous mechanism it is, really isn't a very good example of magnificent grand design. Our bodies are walking natural history museums, full of evolutionary adaptations of varying quality, representing nature's capabilities to adapt, use and reuse evolved structures for different purposes when necessary to advance the cause of survival. Some of those adaptations work pretty well, some just barely. We also have no shortage of body structures once had valuable purposes, but now are no longer of any use to us. Here are some examples:
**Goose Bumps. We all get them from time to time for various reasons. They don't really serve any valuable function now, but they were extremely valuable to our ancestors who had more hair. Not only did they provide insulation between the hair and the skin, but they were capable of making us look bigger and scarier to potential predators or enemies. Next time you get goosebumps, you can offer them a note of thanks for protecting your own direct ancestors from sabre-tooted tigers.
**Jacobson's organ: We all have this small organ in our nose. it once helped us detect pheromones and locate potential mates. We are born with it in a more or less functional state, but early in life its development is arrested and it is now more or less useless. Some companies still market various perfumes and deodorants they claim to contain pheromones to heighten your sexual appeal. But those claims are decidedly lacking in well documented scientific studies. Almost everyone is marginally familiar with Jacobson’s organ. Everyone has seen snakes and other reptiles flicking their tongues in and out. They do this because their tongue captures odor particles carried by moisture in the air. The particles are then transferred to their Jacobson’s organ. This is how snakes smell, and demonstrates our common ancestry with snakes and other reptiles.
**Auriculares muscles: These are muscles in your ears which don't function much anymore, beyond the ability to amuse guests at parties with an unusual talent for wiggling your ears. But if you own a cat, you can quickly see exactly why these muscles exist. A cat can turn its ears nearly backwards from the normal front facing configuration, which enables them to detect and interpret sounds all around them. Our distant ancestors had this capability. We no longer require it, but the now underdeveloped muscles remain present to remind us of our evolutionary past.
**Plantaris muscle: About 90% of humans still have this underdeveloped muscle in their feet, but it is effectively useless to us. Our ancestors used it extensively. It helps the feet grip nearly as effectively as your hands and is extremely beneficial if you spend a lot of your time climbing and living in trees. We have little use for it, so it is either essentially useless or in a minority of cases, entirely absent in your body.
**Wisdom teeth: At a time when our jaws were larger and our diet consisted almost exclusively of plants, wisdom teeth helped us better chew plant matter, aiding in the digestive process. These days, with our smaller jaws, they are primarily used for the enrichment of dentists. Some of us are fortunate enough they are either absent or just never grow in. I was one of the lucky ones in this regard.
**The Appendix: There is still considerable debate as to just what the purpose of our appendix was, but there is no debate about the fact that it is mostly useless to us now. When it becomes infected, doctors remove it without concern and once absent, it poses no issue to the patient who has it removed.
**Recurrent laryngeal nerve: This is actually a system of nerves which runs from your brain to your larynx, regulating its operation. The interesting thing is it only needs to be a few inches long, but this isn't the way it is designed. It runs from your brain down the length of your neck, clear down to your heart, wraps its way around the aorta then back to your larynx. The same nerve system is present in most chordates; giraffes, gorillas, sharks, kangaroos, bald eagles, you name it. Its structure is the same in all of them. It has even shown up in the fossil record and in cases where it is preserved in the extremely long-necked sauropods, its length can reach 95 feet. Some distant ancestor of all chordates probably used this nerve system for a different function. We all still have it and it serves a vital function, but the fact it is several times longer than it needs to be is evidence it once had a different, unknown purpose.
** nipples: Nipples have an important function in mammalian females, who generally are charged with the care and nurture of infants. In males, they serve no purpose whatsoever. But I can use myself again, as an example of how the fact that males have nipples is an interesting piece of evidence for evolution. Below my left nipple is a brown smudge, some might simply dismiss it as a birth mark. My father had it too and claimed it was a spot where a once bit him. But such injuries are not generationally passed. The reality is, the spot is an underdeveloped third nipple. If you examine the same area on my right side, very closely, you can make out the 4th nipple as well. These vestige nipples are more common than you might think: Evidence of a time when our ancestors were likely to produce litters rather than the more common single offspring in modern times. It makes no reasonable sense for males to have nipples at all. It makes even less for males or, for that matter females to carry the evidence of multiple sets of nipples unless they are taken in the context of evidence of our ancestory.
There are numerous other interesting examples in our bodies and throughout nature and the topic is fascinating. But the argument against intelligent design can be carried as strongly by some of the things our bodies can't do as those they can. For example, plants are able to produce food from the process of photosynthesis. All they need is sunlight and water. A similar process would obviously be highly advantageous for us. Instead, we have to rely on other living things, be they fruits, plants or other items to be our food source. It is obviously a highly inefficient, even wasteful way to arrange things, particularly since the sun provides more than adequate energy every day to sustain us. Neil deGrasse Tyson also once joked about the appalling inefficiency of placing the sewage removal system next to the playground.
Belief systems can lock us into antiquated superstitions, rituals, biases, prejudices and can even lead us to do less than what is in our own best interests in hopes some deity will save us from problems of our own creation. Knowledge systems are our best defense against these baser tendencies. There are those who might argue in counterpoint we are all somehow required to respect the beliefs of others, regardless of the level of evidence available to support those beliefs. I am willing to recognize the right of others to their beliefs. I am not willing to recognize that there exists a right to have those beliefs go unchallenged, especially when the challenge is reinforced ideas with superior evidence in support. We are compelled to understand and accept the world and universe we live in on its terms, not on ours.
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