======================================================================

=========================================================================== THE HUMAN EYE IN SPACE by Lambert Parker (edited) ASTRONOMY AND SPACE SIG --------------------------------------------------------------------------- Human visual hardware is a result of a billion years of evolution within the earths atmosphere where light is scattered by molecules of air, moisture, particular matter etc. However as we ascend into our atmosphere with decrease density, light distribution is changed resulting in our visual hardware receiving visual data in different format. Some Aspects to Consider: 1. Visual acuity is the degree to which the details and contours of objects are perceived. Visual acuity is usually defined in terms of minimum separable.Large variety of factors influence this complex phenomenon which includes : # Optical factors- state of the image forming mechanisms of the eye. # Retinal factors such as the state of the cones. # Stimulus factors such as illumina tion, brightness of the stimulus, contrast between the stimulus and background, length of time exposed to the stimulus. * Minimum separable: shortest distance by which two lines can be separated and still be perceived as two lines. "During the day, the earth has a predominantly bluish cast..... I could detect individual houses and streets in the low humidity and cloudless areas such as the Himalaya mountain area.... I saw a steam locomotive by seeing the smoke first..... I also saw the wake of a boat on a large river in the Burma-India area... and a bright orange light from the British oil refinery to the south of the city (Perth,Australia.)" The above observation was made by Gordon Cooper in Faith 7 [1963] and which generated much skepticism in the light of the thesis by Muckler and Narvan "Visual Surveillance and Reconnaissance from space vehicles" in which they determined that a visual angle of ten minutes was the operational minimum, and that the minimum resolvable object length [M.R.O.L] at an altitude of 113 miles would be 1730 ft. This limitation of acuity was revised the next year to 0.5 seconds of arc for an extended contrasting line and 15 seconds of arc for minimum separation of two points sharply contrasting with the background. Orbiting at 237 miles in the skylab it was possible to see the entire east coast [Canada to Florida Keys] and resolve details of a 500 feet long bridge based on inference. Of Interest is the fact that even though the mechanical eye [camera systems] can resolve objects greater than fifty times better than the human eye, without the human ability to infer, interpretation of the data is meaningless. Conclusion: Visual acuity in space exceeds that of earth norm when objects with linear extension such as roads, airfields, wake of ships etc. 2. Stereoscopic vision: the perception of two images as one by means of fusing the impressions on both retinas. In space one has to deal with a poverty of reference points. For hardware evolved in a reference oriented paradigm, this possess a grave problem. Once out of the space craft and gazing outward, the eye can only fix on the stars [without even a twinkle] which for all practical purpose is at infinity ie. without stereoscopic vision "Empty field myopia" prevails. Empty Field Myopia is a condition in which the eyes, having nothing in the visual field upon which to focus, focus automatically at about 9 feet . An astronaut/cosmonaut experiencing empty field myopia focusing at 9 ft would be unable see objects at a range close as 100 ft. If another spacecraft, satellite, meteorite or L.E.M entered his field of vision, he would not be able to determine the size nor the distance. Solution: Man does not face any hostile environment in his birthday suit, the clothing industry and need for walk in closet say it all. In space we will wear our exoskeleton just as we wear winter jackets in winter and we will wear our helmets with visors to maintain our internal environment, filter out all those nasty rads etc. Since Empty Field Myopia is secondary to loss of reference points why not just build them into the visor itself giving the eye points of reference-- create a virtual reality This line of speculation leads to amazing concepts...... To learn more about the concept of virtual universe in ====================================================================== ====================================================================== REPRODUCTION: A-Courting to Nature! LIFE SCIENCES SIG ---------------------------------------------------------------------- For some time she had watched his movements, appearing coyly in his haunts. And now, had it paid off? Doubtless, he was in love. His muscles were taut; he swooped through the air more like an eagle than a Greylag gander. The only problem was, it was not for her that he then landed in a flurry of quacks and wingbeats, or for her that he dashed off surprise attacks on his fellows. It was, rather, for another - for her preening rival across the Bavarian lake. Poor goose. Will she mate with the gander of her dreams? Or will she trail him for years, laying infertile egg clutches as proof of her faithfulness? Either outcome is possible in an animal world marked daily by scenes of courtship, spurning and love triumphant. And take note: these are not the imaginings of some Disney screen-16 writer. Decades ago Konrad Lorenz, a famed Austrian naturalist, made detailed studies of Greylags and afterwards showed no hesitation in using words like love, grief and even embarrassment to describe the behavior of these large, social birds. At the same time he did not forget that all romance - animal and human - is tied intimately to natural selection. Natural selection brought on the evolution of males and females during prehistoric epochs when environmental change was making life difficult for single-sex species such as bacteria and algae. Generally, these reproduced by splitting into identical copies of themselves. New generations were thus no better than old ones at surviving in an altered world. With the emergence of the sexes, however, youngsters acquired the qualities of two parents. This meant that they were different from both - different and perhaps better at coping with tough problems of survival. At the same time, nature had to furnish a new set of instincts which wo uld make "parents" out of such unreflective entities as mollusks and jellyfish.. The peacock's splendid feathers, the firefly's flash, the humpback whale's resounding bellow - all are means these animals have evolved to obey nature's command: "Find a mate. Transmit your characteristics through time!" But while most males would accept indiscriminate mating, females generally have more on their minds. In most species, after all, they take on reproduction's hardest chores such as carrying young, incubating eggs and tending newborns. Often they can produce only a few young in a lifetime. (Given half a chance, most males would spawn thousands.) So it's no surprising that the ladies are choosy. They want to match their characteristics with those of a successful mate. He may flap his wings or join a hockey team, but somehow he must show that his offspring will not likely be last to eat or first in predatory jaws. Strolling through the Australian underbrush that morning, she had seen nothing that might catch a female bowerbird's eye. True, several males along the way had built avenue bowers - twin rows of twigs lined up north and south. True, they had decorated their constructions with plant juices and charcoal. Yet they displayed nothing out front! Not a beetle's wing. Not a piece of flower. Then she saw him. He stood before the largest bower and in his mouth held a most beautiful object. It was a powder blue cigarette package, and beneath it there glinted a pair of pilfered car keys. Without hesitation she hopped forward to watch his ritual dance. Males have found many ways to prove their worth. Some, like bowerbirds, flaunt possessions and territory, defending these aggressively against the intrusion of fellow males. Others, like many birds and meat-eating mammals, pantomime nest building or otherwise demonstrate their capacity as dads. Still others, however, do nothing. Gentlemen may bring flowers, but most male fish just fertilize an egg pile some unknown female has left in underwater sand. For a fish, survival itself is a romantic feat. For other species, though, love demands supreme sacrifices. Shortly after alighting on the back of his mate, the male praying mantis probably had no idea what was in store. This would have been a good thing too, because as he continued to fertilize his partner's eggs, she twisted slowly around ====================================================================== ========================================================================== CHINA CITES 'GREAT PROGRESS' IN MANNED SPACE PROGRAM By Daniel Southerland (c) 1986, The Washington Post PEKING - China has made "great progress" in developing a manned space program and the day it launches a man in space for the first time is "not far off," an official newspaper said Sunday. The overseas edition of the People's Daily, the leading Communist Party newspaper, said China has "already begun the work of choosing its first team of astronauts." Although it gave few details, the article made it sound as though China is preparing to launch its first men into space much sooner than many foreign observers had thought possible. "We have already succeeded in producing life-support systems and in solving the problems of controlling gas composition and pressure in the cabin and the level of heat and humidity," the report said. The report, published Sunday, said the Chinese have developed the largest centri fuge of its kind in Asia and Europe to simulate cabin conditions created by the launching of a spaceship. "The day when a Chinese goes roaming through space is not far off," the report said. On June 5 of this year, Sun Jiadong, vice minister of astronautics, told reporters that China would put a man into space but that such a program "must be worked out gradually in keeping with our needs and capabilities." A foreign observer who has followed the Chinese space program said it could still be a few years before China puts a man into orbit. The People's Daily report did not say how many astronauts are being trained or exactly when they might go into space. The Chinese have appeared to be working for several years on problems associated with building a space shuttle. A high-ranking official of China's national defense, science and technology commission confirmed last May that there had been debate over the feasibility of deploying a space shuttle. According to the China Business Revie w, a magazine published in Washington, D.C., China has been experimenting for more than 10 years with the thermal problems associated with spacecraft re-entry. The Chinese also have been developing space food and space suits for at least seven years, according to published reports. The first publicity about the astronauts began to appear in Chinese magazines in 1980. In early 1980, Science Life magazine, published in Shanghai, described a group of astronauts undergoing fairly sophisticated training, including use of a high-speed centrifuge and a simulated spaceship. Trainees were reported to be wearing airtight spacesuits designed for use on the moon. =============================================================================== ====================================================================== ============================================================================== Your Bones in Space ASTRONOMY AND SPACE SCIENCE ------------------------------------------------------------------------------ Hypogravitational Osteoporosis: A review of literature. By Lambert Titus Parker. May 19 1987. Osteoporosis: a condition characterized by an absolute decrease in the amount of bone present to a level below which it is capable of maintaining the structural integrity of the skeleton. To state the obvious, Human beings have evolved under Earth's gravity "1G". Our musculoskeleton system have developed to help us navigate in this gravitational field, endowed with ability to adapt as needed under various stress, strains and available energy requirement. The system consists of Bone a highly specialized and dynamic supporting tissue which provides the vertebrates its rigid infrastructure. It consists of specialized connective tissue cells called osteocytes and a matrix consisti ng of organic fibers held together by an organic cement which gives bone its tenacity, elasticity and its resilience. It also has an inorganic component located in the cement between the fibers consisting of calcium phosphate [85%]; Calcium carbonate [10%] ; others [5%] which give it the hardness and rigidity. Other than providing the rigid infrastructure, it protects vital organs like the brain], serves as a complex lever system, acts as a storage area for calcium which is vital for human metabolism, houses the bone marrow within its mid cavity and to top it all it is capable of changing its architecture and mass in response to outside and inner stress. It is this dynamic remodeling of bone which is of primary interest in microgravity. To feel the impact of this dynamicity it should be noted that a bone remodeling unit [a coupled phenomena of bone reabsorption and bone formation] is initiated and another finished about every ten seconds in a healthy adult. This dynamic system respo nds to mechanical stress or lack of it by increasing the bone mass/density or decreasing it as per the demand on the system. -eg; a person dealing with increased mechanical stress will respond with increased mass / density of the bone and a person who leads a sedentary life will have decreased mass/density of bone but the right amount to support his structure against the mechanical stresses she/she exists in. Hormones also play a major role as seen in postmenopausal females osteoporosis (lack of estrogens) in which the rate of bone reformation is usually normal with the rate of bone re-absorption increased. In Skeletal system whose mass represent a dynamic homeostasis in 1g weight- bearing,when placed in microgravity for any extended period of time requiring practically no weight bearing, the regulatory system of bone/calcium reacts by decreasing its mass. After all, why carry all that extra mass and use all that energy to maintain what is not needed? Logically the greatest loss -de mineralization- occurs in the weight bearing bones of the leg [Os Calcis] and spine. Bone loss has been estimated by calcium-balance studies and excretion studies. An increased urinary excretion of calcium , hydroxyproline Rapid increase of urinary calcium has been noted after takeoff with a plateau reached by day 30. In contrast, there was a steady increase off mean fecal calcium throughout the stay in microgravity and was not reduced until day 20 of return to 1 G while urinary calcium content usually returned to preflight level by day 10 of return to 1G. There is also significant evidence derived primarily from rodent studies that seem to suggest decreased bone formation as a factor in hypogravitational osteoporosis. Boy Frame,M.D a member of NASA's LifeScience Advisory Committee [LSAC] postulated that "the initial pathologic event after the astronauts enter zero gravity occurs in the bone itself, and that changes in mineral homeostasis and the calcitropic hormones are secondary to this. It appears that zero gravity in some ways stimulate bone re-absorption, possibly through altered bioelectrical fields or altered distribution of tension and pressure on bone cells themselves. It is possible that gravitational and muscular strains on the skeletal system cause friction between bone crystals which creates bioelectrical fields. This bioelectrical effect in some way may stimulate bone cells and affect bone remodeling." In the early missions, X-ray densitometry was used to measure ====================================================================== ======================================================================= Tall Stories NEWSCIENCE ----------------------------------------------------------------------- Picture in your mind the skyline of downtown Toronto. There's the CN Tower, of course, and the 72-floor First Canadian Place, the city's tallest skyscraper. Cascading from there are the assorted banks and hotels and insurance towers. Now, use your imagination to construct some new buildings, these ones reaching three, four and five times higher than the others. Top it all off with a skyscraper one mile high (three times as high as the CN Tower). Sound fanciful? It did 30 years ago when Frank Lloyd Wright proposed the first mile-high building. But not today. We are now said to be entering the age of the superskyscraper, with tall buildings poised to take a giant new leap into the sky. Skyscrapers approaching the mile mark may still be awhile off, but there are proposals now for megastruct ures soaring 900 m -- twice as high as the world's tallest building, the 110-story Sears Tower in Chicago. Suppose that you were asked to erect such a building. How would you do it? What are the obstacles you'd face? What materials would you use? And where would you put it? Building a superskyscraper, the first thing you would need is a considerable slice of real estate. Tall buildings require a large base to support their load and keep them stable. In general, the height of a building should be six times its base, so, for a skyscraper 900-m tall, you'd need a base of 150 square m. That much space is hard to come by in, say, downtown Toronto, forcing you to look for an undeveloped area, perhaps the Don Valley ravine, next to the Science Centre. Bear in mind though that the Don Valley is overlain by loose sand and silt, and tall buildings must stand on firm ground, or else risk the fate of edifices like the Empress Hotel in Victoria. This grand dowager, completed in 1908, lon g before the science of soil mechanics, has since found herself slowly sinking into the soft clay. Soil analysis is especially critical in facing the threat of earthquakes. The Japanese have learned many times the hard way what happens when an earth tremor shakes a high-rise constructed on soft, wet sand. The quake's enormous energy severs the loose connections between the individual grains, turning the ground into quicksand in just seconds and swallowing up the building. . Engineers have actually built machines that condense loose ground. One machine pounds the earth with huge hammers. Another plunges a large vibrating probe into the ground, like a blender in a milk shake, stirring up the sand so that its structure collapses and the individuals grains fall closer together. Anchoring a skyscraper in the Don Valley would best be solved by driving long steel piles down through the sand and silt into the underlying hard clay till. Or, if the clay till lies too far underground , inserting more piles into the sand. The friction between sand and so much steel would then be sufficient to hold the concrete foundation above in place. The next obstacle in erecting a superskyscraper, and perhaps the biggest one, is wind. Tall buildings actually sway in the breeze, in much the same way that a diving board bends under the weight of a diver. Building an edifice that doesn't topple over in the wind is easy enough. The real challenge is keeping the structure so stiff that it doesn't swing too far, cracking partitions, shattering windows and making the upper occupants seasick. As a rule, the top of skyscraper should never drift more than 1/400 of its height at a wind velocity of 150 km/h. Older buildings, like the Empire State Building, were built so that their core withstood all bending stresses. But structural engineers have since found that by shifting the bracing and support to the perimeter of a building, it can better resist high winds. The most advance d buildings are constructed like a hollow tube, with thin, outer columns spaced tightly together and welded to broad horizontal beams. Toronto's First Canadian Place and New York's World Trade Center towers are all giant, framed tubes. A superskyscraper would undoubtedly need extra rigidity, which you could add by ====================================================================== ============================================================================== Your Bones in Space ASTRONOMY AND SPACE SCIENCE SIG ------------------------------------------------------------------------------ Hypogravitational Osteoporosis: A review of literature. By Lambert Titus Parker. May 19 1987. (GEnie Spaceport) Osteoporosis: a condition characterized by an absolute decrease in the amount of bone present to a level below which it is capable of maintaining the structural integrity of the skeleton. To state the obvious, Human beings have evolved under Earth's gravity "1G". Our musculoskeleton system have developed to help us navigate in this gravitational field, endowed with ability to adapt as needed under various stress, strains and available energy requirement. The system consists of Bone a highly specialized and dynamic supporting tissue which provides the vertebrates its rigid infrastructure. It consists of specialized connective tissue cells called osteocytes and a matrix consisting of organic fibers held together by an organic cement which gives bone its tenacity, elasticity and its resilience. It also has an inorganic component located in the cement between the fibers consisting of calcium phosphate [85%]; Calcium carbonate [10%] ; others [5%] which give it the hardness and rigidity. Other than providing the rigid infrastructure, it protects vital organs like the brain], serves as a complex lever system, acts as a storage area for calcium which is vital for human metabolism, houses the bone marrow within its mid cavity and to top it all it is capable of changing its architecture and mass in response to outside and inner stress. It is this dynamic remodeling of bone which is of primary interest in microgravity. To feel the impact of this dynamicity it should be noted that a bone remodeling unit [a coupled phenomena of bone reabsorption and bone formation] is initiated and another finished about every ten seconds in a healthy adult. Thi s dynamic system responds to mechanical stress or lack of it by increasing the bone mass/density or decreasing it as per the demand on the system. -eg; a person dealing with increased mechanical stress will respond with increased mass / density of the bone and a person who leads a sedentary life will have decreased mass/density of bone but the right amount to support his structure against the mechanical stresses she/she exists in. Hormones also play a major role as seen in postmenopausal females osteoporosis (lack of estrogens) in which the rate of bone reformation is usually normal with the rate of bone re-absorption increased. In Skeletal system whose mass represent a dynamic homeostasis in 1g weight- bearing,when placed in microgravity for any extended period of time requiring practically no weight bearing, the regulatory system of bone/calcium reacts by decreasing its mass. After all, why carry all that extra mass and use all that energy to maintain what is not needed? Logically the greatest loss -demineralization- occurs in the weight bearing bones of the leg [Os Calcis] and spine. Bone loss has been estimated by calcium-balance studies and excretion studies. An increased urinary excretion of calcium , hydroxyproline Rapid increase of urinary calcium has been noted after takeoff with a plateau reached by day 30. In contrast, there was a steady increase off mean fecal calcium throughout the stay in microgravity and was not reduced until day 20 of return to 1 G while urinary calcium content usually returned to preflight level by day 10 of return to 1G. There is also significant evidence derived primarily from rodent studies that seem to suggest decreased bone formation as a factor in hypogravitational osteoporosis. Boy Frame,M.D a member of NASA's LifeScience Advisory Committee [LSAC] postulated that "the initial pathologic event after the astronauts enter zero gravity occurs in the bone itself, and that changes in mineral homeostasis and the calcitropic h ormones are secondary to this. It appears that zero gravity in some ways stimulate bone re-absorption, possibly through altered bioelectrical fields or altered distribution of tension and pressure on bone cells themselves. It is possible that gravitational and muscular strains on the skeletal system cause friction between bone crystals which creates bioelectrical fields. This bioelectrical effect in some way may stimulate bone cells and affect bone remodeling." In the early missions, X-ray densitometry was