| Photos of young fans at Forks high basketball and Rod Enos photo . Article on John Dahlgren is continued from web page 93 photo #1408 SEPARATE ITEM - SCIENCE- FUTURE OF SUN--- FUTURE OF SUN--- Survival of Solar System Life long-term Can Future Scientists Prolong Survival of Life in the Solar System by Removing Helium from the Sun to Reduce total Mass and Delay Eventual Over-heating Billions of Years? by John B. Barrett junior address now 113 W. Third St. Port Angeles WA 98362-2824. In l972 Astonomer Carl Sagan published the "dim early sun" hypothesis to the effect that the sun- now about 4.6 billion years old- was cooler when it first reached the stellar Main Sequence than it is today.I asked astrophysicist Hans Bethe his opinion when he gave a historical talk at Harvard spring l995 - he supports this model.If the sun was a few per cent heavier at first and somehow lost mass, it would have been hotter, but such mass loss appears rare among normal Main Sequence stars, and Bethe suggests the fossil record of the earth's climate is supportive.Reporting work begun in Pennsylvania, Ken Caldeira and James Kasting in l992 published in "Nature" and elsewhere calculations suggesting l. that carbon dioxide and greenhouse gases of a thick atmosphere played a central role in keeping the early earth warm enough so that the oceans never have frozen solid, and life has had an uninterrupted history for 3.5 billion years. -2- Carbon dioxide levels have dropped substantially in the past 75-100 million years as the sun very gradually grows warmer, and atmospheric carbon dioxide is fixed chemically to abundant silicate rocks,which extract carbon dioxide gas from the atnosphere. Volcanism 120 million years ago released a great deal of carbon dioxide and oxygen, but in the last30 million years the rise of the Himalayas and other high mountains has exposed more silicate rocks, and now carbon dioxide is well below one half of one per cent of the atmosphere -3- When atmosphere temperature gets around 120 degrees F. (50 C. ) there will not be enough carbon dioxide for ordinary C3 photosynthesis but -4- The C4 KRANZ-anatomy grasses have become abundant in the last fourteen million years and can continue photosynthesis in atmospheres as low as ten parts carbon dioxide per million - so corn, sugar, millet, andropogon and sorghum may be able to survive perhaps a billion years. My proposal is to look for ways to slow the overheating of the sun by finding a way to extract Helium and reduce the sun's total mass. Smaller stars last billions of years longer than large ones - the hotter the star, the shorter its life. Speaking at Harvard recently, James Kasting estimated the sun becomes ten per cent hotter every billion years. A third recent speaker here was Egil Leer, astrophysicist at University of Oslo - he talked on "Coronal Heating and Solar Wind Acceleration." In response to my question, he estiimated only about one millionth of the sun's total energy is carried away by the solar wind, and only one hundred-trillionth of the sun's mass is expelled in a year. The sun is now about 71% hydrogen and 27% helium. A little helium is lost in the solar wind but not much. In a telephone conversation ProfessorDavid Latham astronomer at Harvard points out that larger stars have their mass organized in shells, and the nuclear reactions take place under extreme gravitional pressures in a small central region.Bethe calculated in the l930's that the central temperature of the sun is around ffteen million degrees Celsius.No presently known technology exists for humans to influence the evolution of the sun,but future technologies might yield ways of using magnetism, lasers or possibly technologies undreamed of today. Nanotube materials might be useful. If helium could be removed from the surface of the sun, it would take millions of years for the reduction of helium to redistribute four hundred thousand miles down to the core. The surface temperature of the sun's chromosphere SURFACE is around 5500 degrees C. though slightly cooler temperatures occur in the magnetic disturbances we call sunspots. Archimedes said (in Greek) Give me a place to stand, and I will move the universe."ANONYMOUS said, "The very difficult we do right away. The impossible takes some time."This is not an easy problem, but I believe it is time for diverse scientific specialists to look at the possibility for some sort of solar surgery to extend the life of the OVERWEIGHT future Sun.David Latham says it "might be easier to move the people" - first stop would be Mars, but it is smaller than the earth, and humans quite likely could use fusion power to create atmospheres and air-condition satellites of Jupiter and Saturn. How many centuries will it be before space colonization offers serious relief to overcrowding on earth? I believe fusion research should get high priority to save the earth's environments - reduce danger of plutonium - and fusion power is indispensable for space colonization.Solar studies need priority the sun affect the weather and the ionosphere - Dr.Baliunas at Harvard is looking at solar cycles that could affect climate next century.Helioseismology, the ecliptic, studies of eclipses, orbiting telescopes , X-ray Ultraviolet UV, infrared, spectroscopy all are adding to our knowledge of the sun. In the mid-twentieth century cheerful projections suggested the sun might stay on the Main Sequence another five billion yeasrs. The recent studies suggest that if we avoid asteroids, nuclear wars, and virus pandemics, overheating of the atmosphere could probably stop most plant life in one hundred million years and even specialized grasses in a billion years.Those who value life in the solar system and universe should think of ways to extend the useful life of the sun - the greatest engineering challenge humanity probably will ever face. [second essay:]Future of Life on Earth Researchers at Pennsylvinia State University in l992 published information on the likely future duration of life on earth.Leaders were Ken Caldeira recently at Livermore California, and James Kasting who has remained at Penn State, lectured at Harvard, and had discussions with astronomers. These researchers suggest the sun is gowing gradually warmer, perhaps ten per cent every billion years. In the last hundred thousand years, carbon dioxide fixation by silicate rock has significantly lowered atmospheric carbon dioxide concentration, causing cooler, drier climates and favoring the emergence of grasses with specialized kranz leaf anatomy and the ability to continue photosynthesis at amosphere willl carbon dioxide concentrations down to ten parts per million.They suggest ordinary C3 photosynthesis would cease in one hundred thousand years at earth temperatures rise to arounmd fifty Celsius or 120 degrees Fahrenheit.Grass C4 synthesis might continue around a billion years.Whether this scenario is precise or not, the evidence indicates the sun will eventually overheat. Can future scientists prolong the survival of life on earth? One possiblity is that humans will colonize first Mars, then satellites of Jupiter and Saturn and eventually vast reaches of space.This might permit colonies to be perpetuated, but the majority of humans and earth species would likely perish. With large scale fusion energy, it might be possible to accelerate the earth's revolution around the sun and move its orbit further from the sun--hopefully in a controlled and calculated manner to achieve optimum warmth.The best solution would be to slow the overheating of the sun by removing a portion of the sun's mass, but obstacles are extremely formidable. The escape velocity of matter at the sun's surface is extremely high. It would be useful to have calculations how close to the sun a space ship could orbit without being captured. A critical question would be whether materials can be manufactured that would withstand temperatures at or near the sun's surface. I do not have complete information but believe carbon and tungsten are among the elements that remain solid at highest temperatures on the order of 2000-3000 degrees C., Carbon gradually turns to vapor without a liquid phase. One helpful research line to investigate would be whether special alloys or ceramic or nanotube materials perhaps formed under high pressure could withstand higher temperatures perhaps not forever but long enough so that machinery could operate in near-sun orbits or conceivably in vicinity of sunspots, which are magnetic storms that are somewhat cooler than the general surace of sun perhaps around 5000 degrees Celsius.The properties of a star depend crucially on its total mass. The smallest main sequence stars have a mass eight per cent of that of the sun and are expected to remain on the Herzsprung-Russell Main Sequence around ten trillion years - a thousand times the estimated life expectancy of the sun.These are the smallest fusion-powered stars, as smaller "brown dwarfs" do not achieve sustainable hydrogen fusion temperature.The sun loses a small amount of mass every years through the solar wind, and some other stars with rapid rotation or other peculiarities may eject mass.Technologies to make the sun lose mass are not easy to think of,even in a conjectural theoretical way, but lasers, strong magnetic fields come to mind, or future technologies that may develop as quantum theory and physics are extended in the future.I urge astronomers, physicists, engineers to think if there would be any way to draw matter out of the sun and extend its stable life.Materials specialists might think if there is any way to design structural materials that could survive temperatures of three to six thousand degrees at least long enough for space ships to operate.- JohnB. Barrett 113 W. Third St. Port Angeles WA 98362-2824---High Blood Pressure-Tax Salt in Processed Foods TAX SALT in Processed Foods -High blood pressure kills millions of Americans, especially the elderly and disproportionate numbers of blacks and poor persons who cannot afford unlimited supplies of dairy products and fresh fruits and vegetables. A great many people are salt-sensitive and can control high blood pressure and kidney problems by reducing salt intake. Salt-free canned goods are scarce and expensive. A tax on salt in processed foods would create an incentive for corporations in the food industry to act responsibly in the public interest, as they have for decades failed to do. Medication in many cases would be unnecessary if individuals watch weight and salt intake and get fresh fruits and vegetables. Institutional persons have a particular problem, including residents in nursing homes and hosptials, as well as students, prisoners, and members of the Armed Forces, and those who eat in restaurants, especially fast food establishments. The Food and Drug Administration and the National Institutes of Health and Public Health Service and Department of Agriculture sshould get necessary directives and resources to help reduce high blood pressure, stroke, heart attack, and kidney problems. The President should lend his personal support to the effort. Help poor, blacks and elderly- Consider a tax on salt in processed |
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