THE SOUTHWORTH PLANETARIUM 70 Falmouth Street Portland, Maine 04103 (207) 780-4249 usm.maine.edu/planet 43.6667° N 70.2667° W Founded January 1970 2022-2023: XX Sunrise: 6:34 a.m. Sunset: 6:29 p.m. Civil twilight ends: 6:58 p.m. Sun's host constellation: Virgo the Maiden Moon phase: Waxing crescent (3% illuminated) Moonrise: 8:17 a.m. Moonset: 7:27 p.m. Julian date: 2459850.21 "Worrying is like paying a debt you don't owe." -Mark Twain THE DAILY ASTRONOMER Tuesday, September 27, 2022 Egg to Apple - A Guide to Big History III - Thresholds Part II ____________________________________________________________________________ From this point on, we'll focus on Earth and the human race. In our defense, this planet is the only one on which we know life exists. While we are confident that life proliferates in the galaxy and Universe, our knowledge of that life is limited to merely one example. In time, we will come to know of life elsewhere and as this knowledge expands to life forms at various locations, we'll be able to incorporate the information about these other races into our thresholds. ____________________________________________________________________________ *THRESHOLD FIVE: LIFE* As far as we know, life might have started on Earth about 3.8 billion years ago: almost as soon as conditions were conducive to its development. Although the planet formed about 4.5 billion years ago, its thin, fractured crust lay upon a fire-red molten interior that often shone through fissures lacerating its surface. Moreover, the planet was brutally battered by unrelenting onslaught of smaller bodies during a period known as the Great Bombardment. Only when these assaults abated sufficiently, around the same time the crust cooled enough to produce a stable membrane, did the first life forms develop on Earth. How life formed and the precise time of this formation remains unknown. However, evidence suggests that the first objects we could describe as "living" appeared about 3.8 billion years ago. These were the truly primordial cells, the prokaryotes. [image: shutterstock-1696725337.webp] An idealized image of our antecedent: the ancestor of all the life forms currently thriving on this planet. Smaller than the eukaryotes, the prokaryotic cell lacked a nucleus or organelles that most cells now contain. They were, however, encapsulated in a cell wall, or membrane that separated them from their surroundings. This little object, ladies and gentlemen, occupies the very first rung of the life ladder. This minuscule creature, as far as we know, marks the end point of any creatures' genealogy. The prokaryotes were followed by the eukaryotes, cells with well defined nuclei and organelles. These cells would ultimately give rise the staggering diversity of life we now observe on our planet. Throughout the billions of years of evolution, life forms have divided into three Domains: Bacteria, Archaea and Eukaryota. (We animals fall into the third category.) From there the life forms are subdivided into six kingdoms: Animalia, Plantae, Fungi, Protista, Archaea/Archabacteria and Bacteria/Eubacteria. From there the subdivisions expand exponentially: phylum, class, order, family, genus and species. [image: Eukaryota_diversity_1.JPG] Threshold Five is a vast Universe in and of itself. Throughout natural history, more than four billion species have developed on our planet. Presently, scientists estimate that about 10 million still exist. From the grey wolf to sequoia; the honey bee to hippopotamus, life seems very much the consummate artist equipped with an inexhaustible palette. We'll have plenty to occupy ourselves once we reach this threshold. ____________________________________________ And now we focus on one species: Kingdom: Animalia Phylum: Chordata Class: Mammalia Order: Primates Family: Hominidae Genus: Homo Species: Sapiens Human beings. Although some might describe this focus as conceited as it is myopic, we argue that humans have proven to be of the utmost importance. We've transformed this world more profoundly than any other species. We were the first to launch off its surface and presumably will become the first to explore other planets and star systems. Remember that our aim is to understand how amalgamations of stardust managed to develop into human brains and its variegated products. We must now narrow our focus to the human. _________________________________________ *THRESHOLD SIX: COLLECTIVE LEARNING/HUMANS* Remember when we started this course we asked you to remove your shoes? Now, we ask you to pick up a book, any book, no matter what it is. It could be "Critical Theory Since Plato," "Gravity's Rainbow," or "Bimbos of the Death Sun." No matter the title, the point is that by holding that book you have access to the words and ideas of another human being that have been preserved in such a way so as to persist even after the originator of those ideas perish. [image: Historical_Writing_Systems.jpg] Although conveyance of information through oral communication occurred about 150,000 years ago: 100,000 years or so after the appearance of homo sapiens, writing systems proved a more reliable means of preserving information. It is now believed that writing independently developed in different regions throughout the world, not just Mesopotamia, as once thought. The technology which enabled people to inscribe thoughts arose about 5,000 - 6,000 years ago with the development, for instance, of the cuneiform script used to transcribe words in various languages such as Sumerian, Hittite, Uratian and Luwian.* Today, more than one hundred thousand books are published every day and millions of words are posted on web-sites everyday throughout the world. Human communicate in more than 7,000 languages that are constantly changing and evolving. Despite this proliferation, writing is a recent development. If we could reduce the timeline of the human race to one year, writing would have developed around December 22nd. Yet, writing is essential for collective learning for people today can benefit from the works, thoughts and ideas of those who have long since perished. *THRESHOLD SEVEN: AGRICULTURE* Food. A necessity for all living beings. The advent of agriculture: the ability to cultivate plant matter in such a way as to provide nourishment to communities enabled the establishment of permanent settlements as the lifestyles of hunter-gatherers is necessarily itinerant. Farming, the practice by which seeds could be sown and crops harvested annually could sustain villages and hamlets of ever increasing size as those who worked the land developed more efficient ways of growing food. Eventually, when these food stores became plentiful enough to exceed the demands of a given society, some citizens within that society were free to follow other pursuits that didn't relate the material survival of their communities. When survival was assured through the labor of others, some engaged in more abstract endeavors such as philosophical pursuits: contemplations related to aspects of existence beyond the material. Ruling classes also emerged and with them emperors, kings and all manner of rulers: malignant, benign or somewhere in between. Agriculture gave rise to the societal differentiations that remain with us especially today when such a small percentage of citizens are involved in food cultivation. It must also be noted that the cycle of planting and harvesting necessitated an accurate reckoning of seasonal transitions which, in part, gave rise to the practice of astronomy: watching the sky to observe the migrations of the star patterns which were consistent throughout the year. *THRESHOLD EIGHT: THE MODERN REVOLUTION* The modern world. It is almost beyond dispute that what we term the "modern world" was made possible by the exploitation of fossil fuels. Burn a tree and one can release much of the solar energy that it absorbed through the century or two of its life. Burn coal and oil and one can tap into solar energies accumulated over millions of years. Combine this with the scientific revolution following the enlightenment -a revolution that enabled humans to devise rigid structures and complex machineries- and one can observe how these factors conspired to ultimately create the megacities of modern day.** [image: SL-19-3-image.webp] In this course, we will be moving through each threshold to understand the mechanisms involved to transform the simplest gases into heavier elements into star-orbiting worlds in which the most primitive cells evolved into the unfathomably complex humans that constructed the ultra-modern urban centers that now pockmark our world. We will also come to learn the consequences of our endeavors and how we can attempt to counteract them. This is the over-aching story of existence: that which is responsible for everything today and which will be responsible for that which has not yet occurred. *In reference to the mythological section of "Egg to Apple," Luwian was likely the primary language of the region known as Troy. **Megacities are defined as those with populations exceeding 10 million people. The United States has only two such cities: New York City and Los Angeles. _______________________________________________________ *EGG TO APPLE III: ERIS - THE WEDDING CRASHER* [image: Eris_Antikensammlung_Berlin_F1775.jpg] Eris, the Greek goddess of discord, was trouble with a capital P. Unlike most people saddled with a sullied reputation, Eris earned hers a hundred and one times over. She was, after all, the goddess of discord, also known as the personification of strife. One could ascribe every human disturbance, from the passing tiffs that perturb the tender love of newlyweds to the tectonic tumults of continent-wide conflicts, to that dastardly daughter of night and shadow (a.k.a. Nyx and Erebus). She was the chattering, gossiping, conniving, finger-pointing, giggling, maliciously mischievous relative at the picnic weaving a meandering path of tears, shock and red faced grimaces in her wake. She was the suppurating, burbling sea of toxic froth in the comment sections under blog posts; the one-star review; the stinging proposal rejection; the awkward silence during comedy routines; every censorious glare, persistent misapprehension, rankling injustice and festering bitterness. She diminished every joy, deepened every sorrow, intensified every skirmish, and derived the greatest delight from casting all relationships asunder. Understandably, she had neither temples nor admirers. Nor did she care to have any. She wanted nothing more than strife, discord, and undying enmity among all. Is it any wonder she was the only one excluded from the wedding party held for Peleus and Thetis, a gathering grander than any since that held for Zeus and Hera. Almost everyone was invited: every Olympian, minor deity and demigod. Even spirits of rivers, mountains, trees and meadows were summoned. Only one, Eris, was told to keep away. Of course, had Eris been an introspective sort, she might have pondered on the matter and realized that hers was an understandable exclusion. She likely would have sullied the whole affair like a meal-befouling harpy. However, Eris was decidedly not an introspective sort. This slight infuriated her beyond measure and she was determined to avenge it. She swiftly went to the Garden of Hesperides to fetch one of the golden apples. These gilded fruits were the most enchantingly beautiful orbs to ever spout out of any Earth-rooted tree. Now, we know that a fearsome dragon stood guard over those apples and was known to ferociously defend them against anyone foolish enough to infiltrate the garden. How she managed to elude him and steal an apple is a mystery. Of course, when the dragon watched Eris approaching, he might have said, "Oh Hell, not her," and flown away. Be that as it may, she did manage to steal an apple. While standing just outside the wedding gathering, Eris attached a parchment reading "for the fairest" to the apple and then threw it into the crowd. [image: 6332.jpg] Wedding of Peleus and Thetis Ordinarily, an errant projectile cast into a crowd causes little stir. However, when that glistening apple fell into the wedding party, the happy chatter pervading the ensemble diminished and then quickly subsided altogether. Everyone who caught sight of it was stunned into silence. This silence became rather tense when the three most powerful goddesses, Hera, Athena and Aphrodite, all came forward to claim the apple. For awhile, the three stood over the coveted prize and glared at each other. Eventually, Hera broke the silence by saying, "Let us allow Zeus to decide." Although Athena and Aphrodite both scoffed at the idea, for Zeus was Hera's husband, they could think of no better idea to settle the dispute and relented. However, when they approached Zeus and demanded that he decide which of them should receive the apple, he firmly declined. He well knew the Olympian character - vain, spiteful, unforgiving- and realized that by choosing one goddess he could incur the implacable hatred of the other two. (And considering that they were all immortal, those two would have a long time to hold the grudge). "I have another idea," Zeus said, deftly avoiding his wife's furious glare, "Let us have someone else decide." "Who, dear husband?" Hera demanded. "Hera, my Love, I know the perfect person and, if I am not mistaken, he is out tending his flock." "A shepherd?" Athena spat. "Are you in jest?" "Not in the slightest, dearest Athena. His name is Paris and is known for his honesty and integrity. He will serve as the perfect judge." "Handsome, as well?" Aphrodite asked. "Excruciatingly," Zeus replied. Aphrodite smirked. "Then, let us go see this shepherd." Zeus breathed a deep sigh of relief when the three goddesses vanished. As he turned his attention back to the other gatherers, all of whom resumed their respective conversations, Zeus was convinced that he had behaved judiciously and thought no more of the matter. At the same time Eris laughed silently to herself and departed. She knew that she had caused a stir and in so doing avenged herself against those who excluded her. How much happier she would have been had she realized that she had just set the stage for the greatest war the world had ever known. _________________________________________________________________ To subscribe or unsubscribe from the Daily Astronomer: https://lists.maine.edu/cgi-bin/wa?SUBED1=DAILY-ASTRONOMER&A= <https://lists.maine.edu/cgi-bin/wa?SUBED1=DAILY-ASTRONOMER&A=1>