21 results found containing all search terms.
... Groups ACB10 Orbits of New Comets Diverge from Common Point ACB11 Excess of Retrograde Long Period Comets ACB12 Uranus-Neptune Region Favored as Comet Source ACB13 Cometary Perturbations Suggestive of Planet X ACB14 Rapid Attrition of the Oort Cloud by Molecular Clouds ACB15 Dynamical Improbability of the Oort Cloud ACO OBSERVATIONAL ANOMALIES OF COMETS ACO1 Two-Dimensional Comet Tails ACO2 Cometary Activity Far from Solar Influence ACO3 Comets without Nuclei ACO4 Absence of Meteorites from Comet-Related Showers ACO5 Contraction of Cometary Comas as the Sun is Approached ACO6 Unexplained Abundance of Short-Period Comets ACO7 Persistence of Long-Period Comets Despite Attrition from Molecular Clouds ACO8 Seriality of Cometary Apparitions ACO9 Multiple Tails and Antitails ACO10 Ejection of Spherical Halos ACO11 Correlation of Terrestrial Auroras and the Phenomena of Distant Comets ACO12 Blinking Comets ACO13 The Anomalous Disappearance of Comets ACO14 Anomalous Brightening of ... -of-Approach of Comets to the Sun ACB3 New Comets Have Almost Critical Velocity ACB4 Sun-Grazing Comets: The Kreutz Group ACB5 Changing Cometary Periods ACB6 Jupiter's Family of Comets ACB7 Low-Eccentricity Cometary Orbits ACB8 The Scarcity of Hyperbolic Orbits ACB9 Cometary Groups ACB10 Orbits of New Comets Diverge from Common Point ACB11 Excess of Retrograde Long Period Comets ACB12 Uranus-Neptune Region Favored as Comet Source ACB13 Cometary Perturbations Suggestive of Planet X ACB14 Rapid Attrition of the Oort Cloud by Molecular Clouds ACB15 Dynamical Improbability of the Oort Cloud ACO OBSERVATIONAL ANOMALIES OF COMETS ACO1 Two-Dimensional Comet Tails ACO2 Cometary Activity Far from Solar Influence ACO3 Comets without Nuclei ACO4 Absence of Meteorites from Comet-Related Showers ACO5 Contraction of Cometary Comas as the Sun is Approached ACO6 Unexplained Abundance of Short-Period Comets ACO7 ...
Terms matched: 2 - Score: 236 - 15 May 2017 - URL: /cat-astr.htm
... Science Frontiers ONLINE No. 80: Mar-Apr 1992 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects The Nullarbor Lode For the last few hundred years people have been picking up sparsely strewn meteorites all over the planet. But Antarctic explorers, within the last few decades, found that thousands of meteorites have been concentrated in the ice of the southernmost continent. Even more recently, the desolate, desert-like Nullarbor (" no-trees") Plain, in Southern Australia, has been discovered to be another concentrated source of of meteorites. There may be millions there. The problem is that only 2.9 % of them are iron meteorites, whereas those picked up in recent years around the planet-atlarge are 4.8 ... irons. The meteorites from the Antarctic lode, on the other hand, weigh in with only 2.2 % irons. Why the marked differences? Could it be age? The Antarctic meteorites seem to be up to a million years old; those of Nullarbor, perhaps 16,000-18,000 years. (Anonymous; "A Meteorite Bounty from Down Under," Sky and Telescope, November 1991.) Comment. Perhaps pertinent is the observation that fossil meteorites are essentially nonexistent in geological formations older than a million years. This is an anomaly of itself! From Science Frontiers #80, MAR-APR 1992 . 1992-2000 William R. Corliss ...
Terms matched: 2 - Score: 236 - 15 May 2017 - URL: /sf080/sf080a05.htm
... Science Frontiers ONLINE No. 45: May-Jun 1986 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Disparity Between Asteroids And Meteorites Since the meteorites we pick up on earth (Antarctica and elsewhere) are thought to have come from pulverized asteroids, it is something of a shock to find profound dissimilarities between asteroids and meteorites. "The problem is that while reflectance spectra of some meteorites measured in the laboratory appear to correspond to spectra of various asteroids, the S class, which makes up about half of all asteroids in the inner belt, doesn't appear to match any common meteorite class, and conversely, common meteorite classes (e .g ., Ordinary Chondrites) appear to match only a few asteroids." (Harris, ... Amphitrite Is a Topic of Interest," Geotimes, 30:25, June 1985.) Comment. Note that the visual meteors or shooting stars that burn up high in the atmosphere are believed to be cometary debris (SF#44) and mostly ice and dust. The meteors large and substantial enough to make it through the atmosphere and arrive at the surface as meteorites must have a different source -- something more palpable, such as the asteroids, but the spectral disparities reported above may force a reevaluation of this theory. From Science Frontiers #45, MAY-JUN 1986 . 1986-2000 William R. Corliss ...
Terms matched: 2 - Score: 209 - 15 May 2017 - URL: /sf045/sf045p06.htm
... , organic-rich particles drifting down to earth from cometary debris. These particles, which even carry spacesynthesized amino acids down to the earth's surface, seem likely chemical precursors of life. However, the atmosphere is also a potential source of prebiotic chemicals -- providing energy sources are available. Chyba and Sagan suggest as sources: lightning, ultraviolet radiation, and the shock energy derived from meteorite/asteroid/comet impacts. Together these energy sources, especially ultraviolet light, might synthesize thousands of tons of complex organic compounds each year. (Chyba, Christopher, and Sagan, Carl; "Endogenous Production, Exogenous Delivery and Impact-Shock Synthesis of Organic Molecules: An Inventory for the Origins of Life," Nature, 355:125, 1992. Also: Henbest, Nigel ... pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Life-creation from a different perspective The preceding discussion of life's origin at hydrothermal vents was penned by an oceanographer. Astronomers, it seems, prefer different scenarios. C. Chyba and C. Sagan, in a major review article in Nature, see a two-fold problem: (1 ) identifying the source of the raw materials; and (2 ) identifying the source(s ) of energy required for the synthesis of complex organic chemicals. First, they point to the steady drizzle of tiny, organic-rich particles drifting down to earth from cometary debris. These particles, which even carry spacesynthesized amino acids down to the earth's surface, seem likely chemical precursors of life. However ...
Terms matched: 2 - Score: 201 - 15 May 2017 - URL: /sf080/sf080b10.htm
... : Sep-Oct 1989 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Fossil from mars?Who would have thought that the dreary Antarctic wastes would harbor a piece of Mars, much less a fossil of Martian life? Yet, British scientists, I.P . Wright et al, in Nature, come close to such a conclusion. "The meteorite EETA 79001, which many believe to have originated on Mars, contains carbonate minerals thought to be Martian weathering or alteration products. Accompanying the carbonates are unexpectedly high concentrations of organic materials (defined here as carbonaceous matter that has a low stability towards oxidation, and so combusts at less than 600 C; the term 'organic' does not necessarily imply an origin by biogenic processes.) Although ... carbon isotope composition of these materials is indistinguishable from terrestrial biogenic components, and so cannot be used to assess the source, we argue here that their occurrence in an interior sample of a clean Antarctic meteority militates against a wholly terrestrial origin. A sample of Martian organic materials may thus be available for further study in the laboratory." (Wright, I.P ., et al; "Organic Materials in a Martian Meteorite," Nature, 340: 220, 1989.) But there are many "buts": Meteorite EETA 79001 may not have come from Mars after all, even though many scientists think it did. The organic material in EETA 79001 may have come instead from the comet that supposedly blasted the meteorite into space from the Martian surface, although the carbon-isotope ...
Terms matched: 2 - Score: 186 - 15 May 2017 - URL: /sf065/sf065a04.htm
... Science Frontiers ONLINE No. 45: May-Jun 1986 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Antarctic Meteorites Are Different The thousands of meteorites rescued from the Antarctic ice are markedly different from those collected elsewhere on our planet. First, the Antarctic collections contain rare types that seem to have come from the moon and perhaps Mars. Second, the trace elements in the Antarctic specimens differ substantially from those found elsewhere. Age is a third distinguishing parameter. The Antarctic specimens seem to have been residing on and in the ice for some 300,000 years. Almost all meteorites collected elsewhere are less than 200 years old, having been picked up soon after they fell. The implication is that those extraterrestrial projectiles that have accumulated in Antarctica had ... different source. (Dennison, Jane E., et al; "Antarctic and non-Antarctic Meteorites Form Different Populations," Nature, 319:391, 1986.) Comment. A dedicated catastrophist would ask what extraterrestrial event occurred 300,000 years ago? Did it involve the moon? Was terrestrial life, including humans, affected? From Science Frontiers #45, MAY-JUN 1986 . 1986-2000 William R. Corliss ...
Terms matched: 2 - Score: 184 - 15 May 2017 - URL: /sf045/sf045p05.htm
... Science Frontiers ONLINE No. 101: Sep-Oct 1995 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Alh 84001: a message from mars or perhaps some other planet ALH 84001 is a meteorite picked up in the Allan Hills of Antarctica a decade ago. Its composition and fused crust suggest an extraterrestrial -- origin probably Mars. Space scientists think ALH 84001 was blasted off the Martian surface by an impacting body 14-18 million years ago, based upon its exposure to cosmic rays while circling the sun, edging ever closer to earth. The composition of ALH 84001 tells us curious facts about its place of origin. First, it contains carbonate minerals deposited by water. Second, the carbonate grains are banded, implying the parent rock formation ... washed by water more than once. Third, and most interesting, chemists have found traces of molecules called PAHs, based on interconnected benzene rings. Three sources have been proposed for these PAHs: Terrestrial contamination Prebiotic activity on the planet of origin PAH-bearing comets and/or asteroids impacting the parent planet. Terrestrial contamination has always been a problem in analyzing meteorites, but great care has been taken in recent years, especially with the Antarctic lode of meteorites. In view of these precautions, it seems rather likely that somewhere "out there" life is brewing. (Anonymous; "A Chip Off the Old Mars," Sky and Telescope , 90:12, July 1995.) Reference: See also: Incredible Life for the interesting history of past "discoveries of life in ...
Terms matched: 2 - Score: 169 - 15 May 2017 - URL: /sf101/sf101a03.htm
... last October, astronomer D. Steele announced that comet SmithTuttle is heading towards a possible impact with earth on August 14, 2116. This 3.1 -mile-diameter chunk of ice would have the destructive power of 20 million megatons (1 .6 million Hiroshima bombs). (Anonymous; "Astronomer Predicts Comet Collision," Baltimore Sun, October 26, 1992.) Some recent meteorite impacts. Turning from the dire consequences discussed above, just what sort of astronomical debris actually does hit the earth on a day-to-day basis? Fist-sized meteorites strike our planet about every two hours. These are the ones we read about in the newspapers; and they have left a surprisingly large legacy of damage to human structures. C. Spratt and S. Stephens ... to the Earth than the Moon, and each year about five such objects may hit the planet." (Second reference below.) These startling data come from D. Rabinowitz and coworkers at the University of Arizona, who have been scanning nearby space with a telescope fitted with supersensitive charge-coupled devices (CCDs). They have picked up astronomical objects that have escaped conventional instruments. Several sources have been suggested for this unexpected, threateningly large population of small asteroids: (1 ) debris hurled earthward from collisions within the asteroid belt located between Mars and Jupiter; (2 ) the breakup of a large object formerly in orbit about the earth; and (3 ) fragments blasted off the moon by impacts of large asteroids there. (Kerr, Richard A.; "Earth Gains ...
Terms matched: 2 - Score: 168 - 15 May 2017 - URL: /sf085/sf085a03.htm
... microtekites at the Brunhes-Matuyama magnetic reversal and is, therefore, a "magnetostratigraphic" date. Recent excavations by now seem to confirm R. Fudali's assessment that all tektites and microtektites in the Australasian strewn field are definitely 770,000 years old. (Ref. 3) References Ref. 1. Taylor, S.R .; "Tektites: Some Unresvolved Problems," Meteoritics and Planetary Science , 32:4 , 1997. Ref. 2. Schnetzler, C.C . and McHone, J.F .; "Source of Australasian Tektites: Investigating Possible Impact Sites in Laos," Meteoritics and Plane tary Science , 31:73, 1996. Ref. 3. Fudali, R.; "The Stratigraphic Age of Australites Revisited," Meteoritics, ... :114, 1993. Comment. Still puzzling is why so many Australasian tektites show up in recent sediments. One theory is that humans valued these glassy objects and did some anthropomorphic strewing. Dumbbell- and tear-shaped tektites picked up in Indochina. From Science Frontiers #115, JAN-FEB 1998 . 1998-2000 William R. Corliss ...
Terms matched: 2 - Score: 165 - 15 May 2017 - URL: /sf115/sf115p10.htm
... immense deposits of superficial debris all over our globe ? [Picture caption: Mace-shaped and sand-spike concretions from the Colorado delta] Typical subjects covered: Concretions and geodes * Tektites and microtektites * Erratic boulders and gravels * Polystrate fossils * Bone caves and bone beds * Giant basalt flows * Natural glasses * Surging glaciers * Driftless regions * Stretched pebbles * Crystal inclusions * Rarity of fossil meteorites and tektites * Elevated erratics * Stone rivers and rock glaciers 333 pages, hardcover, $18.95, 80 illustrations, 5 indexes 1990. 1030 references, LC 90-60568, ISBN 915554-24-0 , 7x10 format. Unknown Earth: A Handbook of Geological Enigmas Out of print Hardcover, 833 pages, January 1980, ISBN: 0-915554-06-2 ... especially, lengthy coverages of low-level nocturnal lights (Marfa, Brown Moutnain, Min Min, Nekha, Hessdalen, etc). Topic covered include: Aurora-like phenomena Ball Lightning Diffuse Electrical Discharge Phenomena Lightning Anomalies Low-Level Meteor-Like Luminous Phenomena Nocturnal Lights Marine Phosphorescent Displays 425 pages, hardcover, $24.95, 128 illustrations, Time-of-event index, Source index, First-author index, Subject index, 1660 references. 2001. LC 2001126955, ISBN 0-915554-44-5 . 7 x 10" format Dark Days, Ice falls, Firestorms and Related Weather Anomalies Sorry: Out of Print. No longer available. "Weather" is a composite experience of sight, sound, temperature, and other sensations of the elements. ...
Terms matched: 2 - Score: 157 - 10 Oct 2021 - URL: /sourcebk.htm
... Yucatan and is further marked by widespread biological extinctions. In contrast, the Australasian-tektite event is not only minus an obvious crater but seems to have had scant effect on the earth's cargo of sensitive life forms. It was a strangely "gentle" event despite the rocky deluge of tektites. What really happened? (Paine, Michael; "Source of the Australasian Tektites," Meteorite, p. 24, February 2001. Varricchio, Louis; "Tektite Origins," Meteorite, p. 4, May 2001.) Comment. Was the Australasian-tektite event an encounter with mirror matter, perhaps like Tunguska might have been? We would be derelict not to mention here the claim by J.A . O'Keefe and others that the rain of Australasian tektites ... older event has its craterburied below the Yucatan and is further marked by widespread biological extinctions. In contrast, the Australasian-tektite event is not only minus an obvious crater but seems to have had scant effect on the earth's cargo of sensitive life forms. It was a strangely "gentle" event despite the rocky deluge of tektites. What really happened? (Paine, Michael; "Source of the Australasian Tektites," Meteorite, p. 24, February 2001. Varricchio, Louis; "Tektite Origins," Meteorite, p. 4, May 2001.) Comment. Was the Australasian-tektite event an encounter with mirror matter, perhaps like Tunguska might have been? We would be derelict not to mention here the claim by J.A . O'Keefe and ...
Terms matched: 2 - Score: 151 - 15 May 2017 - URL: /sf136/sf136p09.htm
... visible only to trained eyes. "Still, it is estimated that no fewer than 300,000 such bays, ranging from a few feet across to almost two miles in diameter, dot the East Coast landscape from southern New Jersey to northeastern Florida. One source places the number at more than half a million." Map showing areas of abundant Carolina Bays and frequent meterorite finds. However, meteorites are rare in the areas of the bays. Floyd continues with a brief history of the Carolina Bay region and then reviews some of the theories of origin that have been proposed. Two now-discarded mechanisms of formation invoked: (1 ) immense schools of spawning fish; and (2 ) icebergs stranded as the Ice Ages waned. In presenting today's favorite theory, Floyd quotes ... noticeable because of thick forests and semitropical swamplands. "Highways and modern housing developments have all but obliterated thousands of the bays, leaving them visible only to trained eyes. "Still, it is estimated that no fewer than 300,000 such bays, ranging from a few feet across to almost two miles in diameter, dot the East Coast landscape from southern New Jersey to northeastern Florida. One source places the number at more than half a million." Map showing areas of abundant Carolina Bays and frequent meterorite finds. However, meteorites are rare in the areas of the bays. Floyd continues with a brief history of the Carolina Bay region and then reviews some of the theories of origin that have been proposed. Two now-discarded mechanisms of formation invoked: (1 ) immense schools ...
Terms matched: 2 - Score: 148 - 15 May 2017 - URL: /sf082/sf082g12.htm
... have been the same event that created the recently discovered dust ring between Mars and Jupiter, which is believed to be only a few tens of thousands of years old. The nature of the "event" is not specified. (LaViolette, Paul A.; "Evidence of High Cosmic Dust Concentrations in Late Pleistocene Polar Ice (20,000-14,000 Years BP)," Meteoritics, 20:545, 1985.) References. See our catalog volume The Sun and Solar System Debris for more on the flotsam and jetsam of outer space. This book is described here . Also see the following item on "icy meteors" which is also pertinent. From Science Frontiers #44, MAR-APR 1986 . 1986-2000 William R. Corliss ...
Terms matched: 2 - Score: 148 - 15 May 2017 - URL: /sf044/sf044p12.htm
... of the earth's hydrocarbon deposits (gas, oil, graphite, etc.) are not of biological origin but are formed rather when primordial methane outgases from the planet's interior. A vanishingly small number of geologists buy Gold's theory. Nevertheless, the Swedish State Power Authority and some private investors have been impressed enough to fund a drilling project at the Siljan Ring, a meteorite crater 150 miles north of Stockholm. There are no significant sources of biogenic hydrocarbons nearby, but oil seeps are not uncommon around the Ring. Mainstream theory cannot account for these seeps, but Gold's theory can: primordial methane streaming up through the cracked granite shield is converted, probably with the help of bacteria, into oil and hydrocarbon sludge. "Ridicuous," say the mainstreamers ... Recently, the drilling program, which has reached the 22,000foot level, brought up 60 kilograms of very smelly black sludge with the consistency of modeling clay. The gunk seems to have a biological origin. In addition to the black sludge, the drillers have been encountering increasing quantities of various hydrocarbon gases as the hole went deeper. All very supportive of Gold's hypothesis. Establishment geologists are having difficulties explaining these results. They blame contamination by drilling lubricants and/or the surface oil seeps. Gold discounts these explanations. (Anonymous; "Going for Gold," Scientific American, 259:20, August 1988. Also: Begley, Sharon, and Lubenow, Gerald C.; "Gushers at 30,000 Feet," Newsweek, p. 53, June 27 ...
Terms matched: 2 - Score: 139 - 15 May 2017 - URL: /sf059/sf059p10.htm
... , he was in his boat about eight miles offshore. He watched as a distant object approached across the sky toward the ocean at a high rate of speed, and crossed the bow of his boat at an angle with a "whoosh" (his word). Shortly after, a giant swell made his 41-foot sailboat handle like a large surfboard. Various news sources state that the meteorite, as it is now being called, was anywhere from a meter to 10 feet across. The boater who wished to remain anonymous, gave the professors enough information so that they are hoping that the Navy will retrieve the object, which is presumed to be lying in about 70 feet of water off the Daytona Beach coastline, with plenty of coordinates for locating it." (Stein, ... time of the wave, he was in his boat about eight miles offshore. He watched as a distant object approached across the sky toward the ocean at a high rate of speed, and crossed the bow of his boat at an angle with a "whoosh" (his word). Shortly after, a giant swell made his 41-foot sailboat handle like a large surfboard. Various news sources state that the meteorite, as it is now being called, was anywhere from a meter to 10 feet across. The boater who wished to remain anonymous, gave the professors enough information so that they are hoping that the Navy will retrieve the object, which is presumed to be lying in about 70 feet of water off the Daytona Beach coastline, with plenty of coordinates for locating it. ...
Terms matched: 2 - Score: 139 - 15 May 2017 - URL: /sf084/sf084g12.htm
... uninterupted calcareous pelagic sequence across the Cretaceous-Tertiary boundary reveal that the extinction of planktonic Foraminifera and nannofossils was abrupt without any previous warning in the sedimentary record, and that the moment of extinction was coupled with anomalous trace element enrichments, especially of iridium and osmium. The rarity of these two elements in the crust of the Earth indicates that an extraterrestrial source, such as the impact of a large meteorite may have provided the required amounts of iridium and osmium." (Smit, J., and Hertogen, J.; "An Extraterrestrial Event at the Cretaceous-Tertiary Boundary," Nature, 285:198, 1980.) "Evidence is presented indicating that the extinction, at the end of the Cretaceous, of large terrestrial animals was caused by atmospheric heating during a cometary impact ... the abstracts. "Closely spaced samples from an uninterupted calcareous pelagic sequence across the Cretaceous-Tertiary boundary reveal that the extinction of planktonic Foraminifera and nannofossils was abrupt without any previous warning in the sedimentary record, and that the moment of extinction was coupled with anomalous trace element enrichments, especially of iridium and osmium. The rarity of these two elements in the crust of the Earth indicates that an extraterrestrial source, such as the impact of a large meteorite may have provided the required amounts of iridium and osmium." (Smit, J., and Hertogen, J.; "An Extraterrestrial Event at the Cretaceous-Tertiary Boundary," Nature, 285:198, 1980.) "Evidence is presented indicating that the extinction, at the end of the Cretaceous, of large terrestrial animals ...
Terms matched: 2 - Score: 139 - 15 May 2017 - URL: /sf012/sf012p08.htm
... .S . Wolbach et al. Here is their Abstract: "Cretaceous-Tertiary (K -T ) boundary clays from five sites in Europe and New Zealand are 102 -104 -fold enriched in elemental C (mainly soot), which is isotopically uniform and apparently comes from a single global fire. The soot layer coincides with the Ir layer, suggesting that the fire was triggered by meteorite impact and began before the ejecta had settled." The composition of the hydrocarbons in the sediments points to the earth's biomass (mainly surface vegetation) as the source of the soot. The total quantity of K-T soot is equivalent to that which would be produced by burning 10% of all present terrestrial plant material. (Wolbach, Wendy S., et al; ... Global Fire at the Cretaceous-Tertiary Boundary," Nature, 334:665, 1988.) Comment. Unmentioned in the above article is the possibility that extensive wildfires might have been generated by volcanic eruptions, perhaps accompanied by great electrical storms. The 1988 fires in Yellowstone needed no meteoric impact. Reference. Chemical anomalies in the earth's crust are cataloged in ESC1 in Anomalies in Geology. To order this catalog volume, visit: here . Concentration "spikes" of iridium, elemental carbon and soot at the KT boundary, Woodside Creek, New Zealand. (Adapated from Nature, 334:665, 1988). From Science Frontiers #60, NOV-DEC 1988 . 1988-2000 William R. Corliss ...
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... form of cascades of secondary particles that create complex ionized tracks as they penetrate the dense lower atmosphere. Lightning bolts would tend to follow these precursors along their crooked trails. (Anonymous; "Do Cosmic Rays Trigger Lightning Discharges?" New Scientist, 77:88, 1978.) Comment. Thunderstorm frequency has often been linked to solar activity, and cosmic rays could provide the connection. Could meteorites or "thunderbolts" do likewise? From Science Frontiers #3 , April 1978 . 1978-2000 William R. Corliss ...
Terms matched: 2 - Score: 138 - 15 May 2017 - URL: /sf003/sf003p09.htm
... , 14, 1.3 , and 0.7 million years. Tektites are all quite young! (Smith, Peter J.; "The Origin of Tektites -- Settled at Last?" Nature, 300: 217, 1982.) Comment. Were there no tektite-forming meteor impacts prior to 35 millions of years ago? Is this observation related to the great rarity of meteorites in sedimentary rocks? Just what is different about the past 35 million years? Reference. Twelve tektite "problems" are cataloged at ESM3: in Neglected Geological Anomalies. For more on this book, go to: here . From Science Frontiers #25, JAN-FEB 1983 . 1983-2000 William R. Corliss ...
Terms matched: 2 - Score: 138 - 15 May 2017 - URL: /sf025/sf025p08.htm
... sign due to fluctuations in core turbulence caused by two competing energy sources: heat loss at the mantle-core boundary and progressive growth of the inner core. In concept, the heat lost at the core-mantle boundary might be linked to climate changes and sea-floor spreading. Taking a different tack, D. Gubbins has investigated the possibility that field reversals are triggered by ice ages and meteorite impacts (tektite falls). The physical mechanism here would be the increase in pressure upon the core, which affects the rate of freezing in the outer core, and thus the power available to the core dynamo. Gubbins found that these externally caused pressure changes were too small to explain the polarity changes. However, the parameters involved are not well-known, and external triggers cannot yet ... how these phenomena are linked physically to the geomagnetic field. Part of the problem is that we can only guess at how the geomagnetic field is generated. Let us assume that the earth's magnetic field is created by dynamo action in the planet's fluid core. P. Olson finds analytically that the core dynamo may reverse sign due to fluctuations in core turbulence caused by two competing energy sources: heat loss at the mantle-core boundary and progressive growth of the inner core. In concept, the heat lost at the core-mantle boundary might be linked to climate changes and sea-floor spreading. Taking a different tack, D. Gubbins has investigated the possibility that field reversals are triggered by ice ages and meteorite impacts (tektite falls). The physical mechanism here would ...
Terms matched: 2 - Score: 138 - 15 May 2017 - URL: /sf034/sf034p15.htm
... Science Frontiers ONLINE No. 52: Jul-Aug 1987 Other pages Home Page Science Frontiers Online All Issues Last Issue Next Issue Sourcebook Project Sourcebook Subjects Contents Archaeology Costa rica's neglected stone spheres The calico debate, plus a little editorializing Astronomy Small icy comets and cosmic gaia Carbon in a new comet Meteorites also transport organic payloads Supernova confusion and mysteries "COMPACT STRUCTURES": WHAT NEXT? Biology Nose news Checklist of apparently unknown animals New vertebrate depth record Aggressive mimicry Parasites control snail behavior Geology Do large meteors/comets come in cycles? Complexities of the inner earth Geophysics Concentrated source of lightning in cloud More carolina waterguns More moodus sounds Inside a texas tornado Ship enveloped by false radar echo Psychology Dowsing skeptics converted Do dreams reflect a biological state? ...
Terms matched: 2 - Score: 138 - 15 May 2017 - URL: /sf052/index.htm
