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Dark Visitor, is based on fact that a small black hole may have passed by the solar system in 1929, perturbing Neptune's orbit and tilting, then unknown, Pluto's orbit. (A search for the cause of this perturbation led to the discovery of Pluto, but it is now known that Pluto was not the cause.) This black hole was not observed because black holes do not reflect sunlight. If another one were to pass through our solar system, its gravity could change the earth's orbit and sent the earth into an ice age. Ports would become useless in about one decade as oceans again begin to vacate the continental shelf. This is the scary story Dark Visitor tells. Text samples are presented below so you may evaluate the writing quality. Dark Visitor is a cheap, entertaining, yet educational gift that may interest someone in science, without any "textbook style" teaching.
From first four chapters (mainly historical)
Page 6: Most small, privately-owned, oil tankers no longer ventured far from their harbors. They were under long-term contracts to major oil companies and used only to off load oil from the modern leviathans which were unable to come into many ports. Like their smaller cousins, the tugboats, these older tankers now were condemned to monotonous routines of servitude to large and cumbersome giants. Tugboats were made for their task and proud of their power. They tooted their horns as they worked, but the little tankers, who once freely roamed the seas, showed their depression with rust stains and flaking paint.
Page 15: Karen's great grandfather fled Russia before he was a teenager with two rubles in his pocket and his father's blessing. His older brother, Amiel, who was charged with the task of protecting him, accompanied him. Their father sent them away with the admonishment: "Seek your own Promised Land. - This is not it." There had been one pogrom too many in their village.
P21: Mr. Gildwaser was 55 years old when the market crashed (1929). Although largely undamaged financially, he was not immune to the uncertainties of the times. Amid the social upheaval, he had his own private catharses. ... He decided there were more important things to life than his work. He realized late in life that he wanted a son. He began to go to synagogue more often, but he did not find what he was looking for there. ... Kathleen came from a socially prominent, but now financially ruined family. She was a graduate of Radcliffe University, but had never worked before. ... She was attractive, warm and friendly, but she was also Irish, Irish Catholic. ... Boston society was shocked when their engagement was announced. The bishop refused to marry them. Mr. Gildwaser would not convert nor promise to raise any children as Roman Catholics but he ceased celebrating the holy days. They wed in a civil ceremony late in 1931. Kathleen was only 34. Despite the prognostications of many, the marriage was happy and fruitful. Mr. Goldwater was born in the spring of 1933. ... No one seems to know why Mr. Gildwaser changed his son's name to Goldwater. Perhaps it was at Kathleen's request to make it less foreign sounding.
P36: After a week of pondering what could be wrong, Jack decided that there was nothing wrong with his digitization table or computer program. A large asteroid must have hit Pluto between the time of the USA and South American measurements. ... He was half way though writing a brief note to Email to the CfA's Minor Planet Center when he realized his observations could not be explained by an asteroid collision unless the rotational period of the Pluto / Charon system was also changed. (The asteroid would transfer angular momentum as well as linear momentum to the system.) Returning to the digitization table, he began to use both series of photos to carefully evaluate the rotational period of the system. There was no change. Both sets gave a period of 6.387 days. ... The more he tried to build a consist understanding of what was wrong, the less he understood.
P40: After he sold his younger brother to the Chinese pharmacist, Amiel went straight to the harbor. He quickly found the Star of India, the ship the old man had recommended to him. He asked for the first mate by name and, just as the Chinaman had promised, the first mate took him on as a deck hand. Amiel had never been to sea before but he was strong and quick to learn. They set sail for Bombay two days later.
During his walk to the harbor, Amiel had wondered if everything was foreordained, perhaps even foretold -- Why else was his brother named Joseph? -- He felt guilty, but he had had no other choice. All they had eaten in the last four days was two small loafs of stolen bread and a few onions they had gleaned from a field near Copenhagen. Amiel told himself that when he could, he would return and buy back his brother's freedom, but he still felt guilty.
From chapters 5 & 6 (mainly about climate)
P45: I will start the explanation with a simplified earth, the way George did for me. Imagine that the earth did not rotate. How would climate move the excess equatorial heat towards the poles?
Everyone has seen smoke rising and most have seen hot air balloons, at least on TV. Air expands when it is heated and then rises. Some colder air must replace it near the surface. The colder air could come from under a near-by cloud. (The sun is not heating this air in the cloud's shadow, so it is colder.) This cooler air could descend to replace the rising warm air; (and probably would), but that is local weather, not climate. From a climate point of view, the colder air comes from a latitude closer to the poles. ... Air near the surface would be moving towards the equator and gaining heat as it does so. The higher altitude air would be moving towards the poles and losing heat. That is, the prevailing surface winds would come from the north in the Northern Hemisphere if the earth did not spin. - Note: The web page link below about physics and climate gives the next paragraphs that clearly explain why wind and weather usually comes from the west in the USA. Another web page reproduces some graphs and comments from Chapter 12.
P63: The heavy snows that fall during the North's mild winters will not fully melt during the following cold summer, when the earth is farther from the sun. It is this failure to fully melt in summer that causes the ice to accumulate annually until the oceans are smaller -- levels below the continental shelf. The summer of the Southern Hemisphere will be both hot and very humid. Great sheets of extremely thick ice will accumulate only in the Northern Hemisphere. As the ice cover grows, it will spread southward more rapidly because much of the weak summer sun's radiation will be reflected back into space by the continental ice sheet growing southward more each year. (Ice reflects about 85+5% of the sunlight incident upon it.) That is, the cold northern summers will become colder and melt even less ice with each passing year.
Eventually all of the ice now in Antarctic and at least the top two hundred feet of the oceans will be stored on the land as ice in the Northern Hemisphere. In some locations, parts of north-western Europe and some parts of western Canada and adjoining parts of Alaska, this ice will become more than one mile thick! In California the ice will be less thick, perhaps only a few thousand feet where San Francisco was, but the weight of the ice will probably trigger earthquakes in the San Andreas Fault system. It is possible that the dark visitor will indirectly level San Francisco before it buries it under ice.
Dark Visitor describes how these climatic changes are produced by an approaching black hole. Learn more about Dark Visitor at the following specific links:
Dark Visitor is only $12 at Amazon.com, if slow downloading annoys you.
Questions / comments to: Local_Black_Hole@Yanhoo.com
Text from chapters 7 through 12 (Jack's report)
P83: The rotational period of the moon is slowly changing primarily because much of the earth's surface is covered with water. Some of the change is due to the fact that the moon is relative large (compared to all other planet/moon systems) and thus has some "tidal" effect even upon the "solid" earth. Despite the earth's distance from the moon, the moon is actually flexing the solid part of the earth but most of the dissipation of energy is in the ocean's tidal currents. As energy is being removed from the earth / moon system by tidal dissipation, the moon is slowing down and moving farther away. Long ago the moon was much closer to the earth and thus had a shorter period of revolution. When the moon was much closer, the tides were much larger, perhaps nearly a hundred feet of variation in the sea levels at the shore twice each day. The days were less than 24 hours then so high tide came more often. Clearly life forms that were well adapted to swimming were favored during the early history of the earth.
P87: If some intelligent creatures living near another star were to witness our sun in this "red giant" phase, they are not likely to call it (even in their language) the equivalent of "red giant" because the sun is not red, blue or any other color. Color is not a property of any object. - If you doubt this and continue to think the sky is blue, the sun is orange, apples are red, etc. then imagine that thousands of years ago a virus killed all people on earth except those whose DNA coded for daltonism (the most common form of color blindness - people that see objects most people call red as green). Then all the people living on earth today would agree that a star in this phase should be called a green giant because it is green in color, just as green as their hemoglobin blood, but for the sake of clarity, the common erroneous practice of assigning colors to objects will be continued.
Stellar evolution as briefly outlined in Dark Visitor:
When a typical star, like our sun, has converted all of its core hydrogen to helium, the production of energy by nuclear fusion in the core stops and its core begins to contract. Some nuclear fusion continues in a series of thin shells surrounding the core, which are still rich in hydrogen, until they too have exhausted their supply of hydrogen. The surrounding shell of "burning" hydrogen combined with the conversion of gravitational potential into heat by the collapsing core makes the core hotter. As the successive shells burn hydrogen, more helium is produces and falls in upon the core compressing and heating it further. It was already much hotter than "white hot" (nearly 10^8 degrees K) but typically the core does not get hot enough to "burn" the helium core into other elements. To do this, a bigger star with more gravitational energy is required.
Hot electrons limit the contraction of the core of a typical star to 1.4 solar masses or less. The details of this physic are complex but the basic idea is simple. As the densely packed electrons (which at these temperatures do not belong to any particular nucleus) bounce off each other they exchange energy and maintain a distribution of velocities that can be characterized by a single parameter, the temperature. The heavier nuclei do the same thing and these two temperatures are the same.
Temperature is the average energy of motion, but to have the same average energy as the nuclei the relative light electrons must move much faster. As the core contracts and heats, the pressure builds to resist further contraction, initially in direct proportion to the temperature (and density), but as the electron velocities approach the speed of light the pressure increases dramatically, preventing further contraction. This process and the initial mass of the star divide stellar evolution into three broad classes. Most stars keep these relativistic electrons in their core and evolve into "dwarf stars."
More massive stars develop such high pressures upon the core that the electrons are forced to combine with nuclear protons, converting them into neutrons. Neutrons have no electrical charge so they do not resist further contraction as effectively as the charged protons did. These neutron cores contract until the very strong but short-range nuclear forces prevent further contraction. Then the core is one gigantic mass of nuclear (not ordinary matter) density and stellar evolution has produced a "neutron star" which typically is also a "pulsar" for many years.
If the star was very big, it can produce a core so massive that even the short ranged nuclear forces are not strong enough to resist the gravitational burden of the weight of the outer layers pressing down upon the core. The collapse continues. When this collapsing core reaches half the radius it had at the time when gravity first began to overcome the nuclear forces, the outer layers of the core weight four times more. (Gravity is an inverse square law force.) So the collapse accelerates. There is no limit to this process. As the core shrinks, the battle between the nuclear forces and gravity tilts more and more in gravity's favor. It is hard to believe, but true, that just before the end of this process the entire star is smaller than the period which ends this sentence. No magician ever truly made a rabbit disappear, but nature is constantly making entire stars disappear. We call a mass collected into a point of zero size a "black hole."
Thus three evolutionary paths are possible for stars. The typical star dies as a dwarf star. A more massive star as neutron star. Very massive stars produce black holes.