101 results found.
... 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, Alan W.; "Asteroid 29 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 ...
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... Science Frontiers ONLINE No. 37: Jan-Feb 1985 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects More Doubts About Asteroids In an apparent reaction to the stampede to climb aboard the extinction-by-asteroid bandwagon, dissenting papers have begun to appear in the scientific literature. For example, Van Valen's list of objections to the hypothesis of asteroid impact at the Cretaceous-Tertiary boundary was reproduced in the last issue of Science Frontiers. Now, in a recent issue of New Scientist, T. Hallam raises still more objections: Tropical plants, mammals, crocodiles, birds, and benthic invertebrates were little affected by whatever happened at the Cretaceous-Tertiary interface. Furthermore, many groups that were extinguished were already well into a decline. Some geologists insist that some of the supposedly synchronous extinctions were probably separated by several hundred thousand years; viz., plankton and dinosaurs. The vaunted iridium anomaly in deep-sea cores is spread through a considerable thickness of sediment. Even after allowing for the mixing of sediments, the iridium-rich layer is thousands of years thick. According to the asteroid scenario, the clay layer separating the Cretaceous from the Tertiary should represent the fallout from impact-raised dust, which would include asteroidal material and a mixed sample of earth rocks. However, in Denmark, the boundary is marked by the so-called Fish Clay, which is almost pure smectite -- a single mineral and not a mixture of terrestrial rock flour. If it wasn't an asteroid impact, why the ...
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... Science Frontiers ONLINE No. 87: May-Jun 1993 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Cosmic Soot And Organic Asteroids Just as we were getting used to carbonaceous chondrites and tarry comets, we have been hit with cosmic soot and organic asteroids. Truly, it seems as if the universe is one vast factory of complex chemicals. This is not a trivial observation, for it betrays a synthesizing, efflorescent cosmos rather than a universe slowly succumbing to the deepfreezing Second Law of Thermodynamics. Any of these soots and tars wafting down upon the surface of a suitable planet might initiate or accelerate life processes. Cosmic soot. A 70-year-old astronomical enigma is the origin of the DIBs (Diffuse Interstellar absorption Bands). These dark absorption bands in stellar spectra have never been correlated with known chemical compounds. Now, L. Allamandola and F. Salama (NASA-Ames) find that the DIBs may be due to polycyclic aromatic hydrocarbons! A more digestible descriptor would be "soot," like that found in automobile exhaust and on your barbecued steak. (Weiss, Peter; "Cosmic Soot Fills Space between the Stars," New Scientist, p. 15, March 13, 1993.) Organic asteroids. Some asteroids are abnormally red. Newly discovered asteroid 5145 Pholus is 3 times brighter at near-infrared wavelengths than it is in the visible portion of the spectrum. The best explanation so far for this redness is that 5145 Pholus is veneered with organic compounds called "tholins." Tholins are synthesized ...
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... Science Frontiers ONLINE No. 60: Nov-Dec 1988 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Asteroids That Turn Into Comets Even though Chiron is large (about 200 kilometers in diameter) and a bit dark for a rocky asteroid, astronomers have been quite comfortable with calling it an asteroid. True, its orbit between Saturn and Uranus is unusual, but what else could it be but an asteroid? A comet, that's what! Recently, the brightness of Chiron has doubled, suggesting that it has expelled considerable gas and dust -- a characteristic of comets, according to mainstream thinking. Another peculiar aspect of the phenomenon is that Chiron is now located 12 A.U . from the sun (12 earth orbits out). Conventional wisdom has it that solar heating is too weak at that distance to vaporize cometary ices. However, other comets, such as Schwassmann-Wachmann 1, have displayed comas even farther away from the sun. Thus, we have two possible anomalies here: (1 ) The existence of a huge cometlike asteoid in a peculiar orbit (2 ) A mechanism that expels gas and dust from comets at great distances from the sun. The blurring of the distinctions between asteroids and comets is aggravated by the recognition that some other asteroids produce streams of particles that create meteor showers; that is, some asteroids are not merely associated with meteor streams, they actually create them, just as comets expel ice and rocky debris. Some bold astronomers now ask whether asteroids are all burntout comets. ...
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... Science Frontiers ONLINE No. 5: November 1978 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Asteroids with moons?Several recent observations made of asteroids as they occult stars suggest that some asteroids are circled by moonlets. The observational technique used resembles that employed in the discovery of the now-famous rings of Uranus. Briefly, the star being observed blinks out not once in a clean-cut fashion but in a complex scenario that may indicate the presence of a second body. To illustrate, during the 1975 occultation of a star by the asteroid Eros "all sorts of people saw things," meaning secondary events or extra dimmings. Another kind of supporting evidence comes from the light curve of 44 Nysa, which closely resembles that of an eclipsing binary star. (Anonymous; "Asteroids with Moons?" Science News, 114:36, 1978.) From Science Frontiers #5 , November 1978 . 1978-2000 William R. Corliss ...
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... Science Frontiers ONLINE No. 127: Jan-Feb 2000 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Nuclear bombs will not save the earth!Not too long ago, geologists adamantly denied that there were any large meteor craters pockmarking our planet. Now, they find 100-kilometer craters on a regular basis. And scientists are casting worried looks at those near-earth asteroids, knowing that one day one will be on a collision course. Not to worry, say the modern-day Technocrats, we will launch nucleararmed rockets that will nudge such cosmic threats into harmless trajectories. These Pollyannas are presumptious. They assume that asteroids are hard, cohesive objects that will be shoved aside by a few megatons of explosive energy. There are two things wrong with this idea, and these reveal how radically our ideas about the nature of asteroids have changed in just 10 years. First, most astronomers will now agree that asteroids are orbiting rubble piles rather than monolithic objects. For example, the near-earth asteroid Mathilde, 53 kilometers in diameter, has a density of only 1.3 grams/cubic centimeter. Its porosity must be greater than 50%. It is not a hard, coherent object. Instead of a bullet, it is more like a cloud of shotgun pellets. It would be hard to divert all this debris with a nuclear blast. To make matters worse, asteroids like Mathilde are stickier than a cloud of buckshot. This fact is deduced from photos of asteroids showing many to be marked by huge craters ...
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... Science Frontiers ONLINE No. 95: Sep-Oct 1994 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Comets, asteroids, or neither?Like supernova 1987A, also mentioned in this issue, comet P/Shoemaker-Levi-9 is generating headlines in the scientific and popular media. Everyone expected that the impact of this comet on Jupiter would provide us with some very interesting phenomena, but most thought that the debris kicked up by the impacts would reveal something new about Jupiter -- not about comets, since everyone knows what they are! Instead, the long-held theory that comets are simply dirty iceballs is now questioned. Shoemaker-Levi-9 was originally classified as a comet because: (1 ) Its fragments all appeared to be surrounded by comas like all well-behaved comets; and (2 ) It was easily torn apart by Jupiter's strong gravitational field as it narrowly missed Jupiter in 1992. This is just what one would expect from a loosely compacted dirty iceball. But doubts about Shoemaker-Levi-9 's true nature have arisen because of two observations: (1 ) No water vapor has been detected in the plumes thrown up by the impacts of the fragments; and (2 ) The comet's Fragment M, which was supposed to have vaporized in 1993, as comets are wont to do, apparently did not and left a scar on Jupiter like the other fragments. So, Shoemaker-Levi-9 had no discernible ice (unlike comets; it was fragile and ...
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... Science Frontiers ONLINE No. 135: MAY-JUN 2001 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Asteroid Ponds, Beaches, And Boulders Once considered only dull, nondescript vagabonds of the solar system, asteroids are turning out to be rather mysterious and surprisingly complex bits of celestial real estate. The close-up photos of the asteroid Eros (35-kilometers long) from the spacecraft NEAR-Shoemaker have added two new phenomena to the list of asteroid enigmas. Boulders. Eros is covered with huge boulders -- perhaps a million of them over 8-meters wide. The boulders are likely just accreted solar-system debris; but why are they strewn naked on the surface of Eros instead of being intermixed with other rocky debris? Speculation is that the large boulders were coaxed to the surface preferentially over the eons by seismic vibrations -- said vibrations being caused by multitudinous impacts. This type of jostling action also explains why Brazil nuts greet you when you open a well-travelled can of mixed nuts! Ponds and beaches. The fine debris coating Eros may also have responded to the same vibrations, but in different ways. It sort of "flowed" downhill to form curious flat features resembling ponds. Between the ponds and rough terrain, the fine debris has also built up transition zones that look like beaches. Cormell's J. Veverka isn't betting on any of the proposed theories as yet. He declared: We're facing processes we're not familiar with. I truly don't ...
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... Science Frontiers ONLINE No. 85: Jan-Feb 1993 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Heavy traffic in near-earth space That region of outer space near the earth carries a heavier load of flotsam and jetsam than scientists expected. The devastation of the 1908 Tunguska impact in Siberia warns us that this space debris -- meteors, comets, asteroids -- is an active threat. A recent spate of articles paints an ominous future. The earth's retinue of mini-asteroids. "Asteroids as big as houses pass near the Earth 100 times more often than anyone suspected. On an average day, about 50 asteroids measuring at least 10 metres across come closer 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 a Retinue of Mini-Asteroids," Science, 258 ...
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... Science Frontiers ONLINE No. 86: Mar-Apr 1993 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Cosmic Snowballs And Magnetic Asteroids The genesis of a cosmic "dust bunny". The nebulous meteor of July 29, 1970, as observed over Dover, England. The great diversity of the debris swirling around the solar system is making life difficult for scientists trying to reconstruct solar-system history. At the high end of the density spectrum, we now have an asteroid that seems to be mostly metal (probably iron). This is the asteroid Gaspra, some 13 kilometers across, that the Galileo spacecraft encountered in August 1992 on its way to Jupiter. Scientists had not expected Galileo's magnetometer to flicker as it passed Gaspra at a distance of 1600 kilometers -- but it did. In fact, considering the inverse square law and Gaspra's small size, it was a magnetic wallop. Thus, Gaspra is the first known magnetic asteroid; and it is probably mostly metal. (Kerr, Richard A.; "Magnetic Ripple Hints Gaspra Is Metallic," Science, 259: 176, 1993.) At the low end of the density spectrum, we now find that Pluto's moon, Charon, and some of Saturn's moons have very low densities (1 .2 -1 .4 ), meaning they are probably mostly water ice. Such density figures come from direct observation of these objects' volumes combined with mass estimates from their orbital dynamics. (Crosswell, Ken; " ...
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... Science Frontiers ONLINE No. 26: Mar-Apr 1983 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Punching A Hole In The Asteroid Hypothesis Scientists have long searched for a cause for the profound geological and biological changes that apparently occurred between the Cretaceous and Tertiary periods. When an iridium-rich layer was found in several areas at this important boundary, many claimed it as proof of an asteroid impact or some other catastrophism that would nicely explain the massive worldwide changes that occurred. With this preamble in mind, consider the following abstract from an article in Science: "Analyses of the clay mineralogy of samples from the Cretaceous-Tertiary boundary layer at four localities show that the boundary clay is neither mineralogically exotic nor distinct from locally derived clays above and below the boundary. The significant ejecta component in the clay that is predicted by the asteroid impact scenario was not detected." (Rampino, Michael R., and Reynolds, Robert C.; "Clay Mineralogy of the Cretaceous-Tertiary Boundary Clay," Science, 219:1983.) From Science Frontiers #26, MAR-APR 1983 . 1983-2000 William R. Corliss ...
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... Science Frontiers ONLINE No. 73: Jan-Feb 1991 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Asteroid impact or volcanos?The debate over the real cause of the terrestrial catastrophism that occurred at the Cretaceous-Tertiary boundary, some 65 million years ago, grinds on. Some physical scientists claim rather imperiously that the dinosaurs and many other species were done in by the impact of a huge asteroid/meteorite. The worldwide iridium spike is conclusive, they say. Many paleontologists and geologists, however, remain unconvinced and prefer widespread volcanism. We have already covered the various arguments in past issues of Science Frontiers; here, we want to advise our readers that a pair of excellent articles by principals in this debate have appeared in Scientific American. Generally speaking, it seems that the proponents of the impact theory are now listening to the other side. For example, multiple impacts are now proposed to account for evidence of the type introduced below. (Alvarez, Walter, and Asaro, Frank; "An Extraterrestrial Impact," Scientific American, 263:78, October 1990. Also: Courtillot, Vincent E.; "A Volcanic Eruption," Scientific American, 263:85, October 1990.) A spike dulled. The case for a single asteroid/meteorite impact has been weakened by a recent reexamination of the classic exposure of the CretaceousTertiary boundary at Gubbio, Italy. Here, the discovery of an iridium "spike" at the boundary was thought to betoken a sudden, catastrophic, extraterrestrial event. On further ...
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... Science Frontiers ONLINE No. 94: Jul-Aug 1994 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects The shattering of 951 gaspra 951 Gaspra is an irregular asteroid with an average radius of 6.1 kilometers. Located at the inner edge of the main asteroid belt between Mars and Jupiter, Gaspra is believed to be composed mainly of olivine, pyroxene, and nickel-iron. Shape model of Gaspra showing the locations of the grooves. On October 29, 1991, the Galileo spacecraft swept past 951 Gaspra at a distance of 1600 kilometers, snapping photographs as it went. J. Veverka et al report below on what the photos showed: "We report the discovery of grooves in Galileo high-resolution images of Gaspra. These features, previously seen only on Mars' satellite Phobos, are most likely related to severe impacts. Grooves on Gaspra occur as linear and pitted depressions, typically 100-200 m wide, 0.8 to 2.5 km long, and 10-20 m deep. Most occur in two major groups, one of which trends approximately parallel to the asteroid's long axis, but is offset by some 15 , the other is approximately perpendicular to this trend. The first of these directions falls along a family of planes which parallel three extensive flat facets identified by Thomas et al. The occurrence of grooves on Gaspra is consistent with other indications (irregular shape, cratering record) that this asteroid has evolved through a violent collisional history." (Veverka, J., et al ...
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... Science Frontiers ONLINE No. 59: Sep-Oct 1988 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Did an asteroid impact trigger the ice ages?Asteroids and comets are being blamed these days for more and more of our planet's catastrophism -- biological, meteorological, and geological. What a turnabout in scientific thinking in just a decade. F.T . Kyte et al have now provided additional details on meteoritic debris they first described in 1981. On the floor of the southeast Pacific, about 1400 kilometers west of Cape Horn, about 5 kilometers down, they found high concentrations of iridium in Upper Pliocene sediments about 2.3 million years old. Since the proposed projectile hit in very deep water, no crater was dug out. What did survive is called an "impact melt." This is debris rich in noble metals, such as iridium, and contains particles typical of a low-metal mesosiderite. Some 600 kilometers of the ocean floor received this debris. Kyte and his associates estimate the size of the impacting object at at least 0.5 kilometers in diameter. No biological extinctions are correlated with the 2.3 -million-year date, but there appears to have been a major deterioration of climate at about this time. There was a shift in the marine oxygen isotope records and, more obvious, the creation of the huge loess (sandy) deposits in China. What the impact may have done is to vaporize enough water into the atmosphere to increase the earth's albedo, ...
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... of Anomalies (Subjects) Strange reports * Bizarre biology * Anomalous archaeology From New Scientist, Nature, Scientific American, etc Archaeology Astronomy Biology Geology Geophysics Mathematics Psychology Physics Catalog of Anomalies (Subjects)Overview Astronomy Biology Chemistry/Physics Geology Geophysics Logic/mathemitics Archeology Psychology Miscellaneous phenomena Other pages Home Page Science Frontiers Online Science Frontiers: The Book Sourcebook Project A ASTRONOMY Catalog of Anomalies (Astronomy Subjects)Within each of these fields, catalog sections that are already in print are given alphanumerical labels. For example, BHB1 = B (Biology)+ H (Humans)+ B (Behavior)+ 1 (first anomaly in Chapter BHB). Some anomalies and curiosities that are listed below have not yet been cataloged and published in catalog format. These do not have the alphanumerical labels. AA ASTEROIDS AAB CELESTIAL MECHANICS PROBLEMS WITH ASTEROIDS AAB1 Anomalous Asteroid Orbits AAB2 Asteroid Distribution Anomalies AAB3 The High "Internal Energy" of the Asteroid Population AAB4 Peculiar Distribution of Asteroid Spin Rates AAB5 Unexplained Residual Precession of Icarus AAB6 Evidence against an Explosive Origin for Asteroids AB SOLAR SYSTEM "LAWS" AND INTERRELATIONSHIPS ABB DYNAMICS OF THE SOLAR SYSTEM AS-A -WHOLE ABB1 Solar-System Instability ABB2 Circularity of Planetary Orbits ABB3 Anomalous Split of Angular Momentum between Sun and Planets ABB4 Ubiquity of Resonances in the Solar System ABS REMARKABLE RELATIONSHIPS AMONG PLANETARY AND SATELLITE PARAMETERS ABS1 Solar System Laws of Distance ABS2 Similarity of Densities of Composite Terrestrial Planets ABS3 Multiple Primaries in the Solar System ABS4 Supposed Quantization of Planetary Orbital Periods ABS5 Solar System Mass Laws ABS6 The Quantized Nature of Orbital Systems AC COMETS ACB ORBITAL ANOMALIES OF COMETS ACB1 ...
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... Science Frontiers ONLINE No. 128: MAR-APR 2000 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Burps of Death Not only did the poor dinosaurs have to contend with an asteroid impact and a lurch of the poles, but also with the possible ignition of voluminous methane burps. 65-million years ago. This was the time of the well-publicized, but still hypothetical, asteroid impact. It is said to have wreaked havoc on our wounded planet and, especially, the dinosaurs. Volcanos spewed out vast lava fields and filled the air with greenhouse gases and dust. It was a bad time for many life forms. Actually, It may have been far worse than generally advertised. In addition to the volcanic activity and climate change, the shock of the asteroid impact could have been sufficient to destabilize the immense amounts of methane hydrate that have long been locked up, frozen and dormant, in oceanic sediments all over the world. According to this scenario, once the shock of the asteroid impact released the methane from its icy prison, it rose to the surface of the oceans in a world-wide burp. Methane, unfortunately for the dinosaurs and many other life forms, is highly flammable. Lightning could have ignited it almost immediately if it was concentrated enough. A colossal firestorm might have then enveloped the entire planet. The whole atmosphere could have been afire. This, according to B. Hurdle and colleagues at the Naval Research Laboratory, who speculate that the dinosaur hegemony may ended suddenly in flames rather than ...
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... Science Frontiers ONLINE No. 43: Jan-Feb 1986 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Everglades astrobleme?Astrobleme means "star wound," and the southern tip of Florida seems to have been wounded by an asteroid or some other celestial projectile. At a recent meeting of the Geological Society of America, E.J . Petuch proposed that the Everglades region received a direct hit from an asteroid about 36 million years ago. The Everglades region is a swampy, forested area surrounded by an oval-shaped system of ridges. Geologists usually maintain that the Everglades represent a collapse feature caused by groundwater dissolving away limestone. (Buildings and cars seem to be swallowed fairly regularly by Florida sinkholes.) Petuch disagrees with the collapse theory and points to the following evidence for an impact origin: 1. The presence of a strong positive magnetic anomaly; 2. Eocene formations, 40 million years old, are missing over the southern Everglades; 3. A network of fractures pervades rock layers older than Eocene; 4. High iridium concentrations, probably of extraterrestrial origin, exist at the Eocene-Oligocene boundary on nearby Barbados; and 5. The oval reef structure that seems to have grown around the impact area as sealevels rose. Some geologists do not concur with the asteroid theory, but they are all reviewing Florida's geological history in a new light. (Weisburd, S.; "Asteroid Origin of the Everglades?" Science News, 128:294, 1985.) Reference. Very large craters and astroblemes ...
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... Science Frontiers ONLINE No. 63: May-Jun 1989 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects More confusion at the k-t boundary Just a few years ago, many scientists, especially physicists and astronomers, considered the Book of Science to be closed in the matter of what happened at the Cretaceous-Tertiary (K -T ) boundary, 65 million years ago, and why the dinosaurs met their end. It was declared, rather imperiously, that a large asteroid had impacted the earth, causing much physical and biological devastation. Many scientific papers are still being written on this singular period in the earth's history, and the situation is no longer so clear-cut. We select for brief review four papers, each with a different perspective. Occurrence of stishovite. Stishovite, a dense phase of silica, is widely accepted as an indicator of terrestrial impact events. It is not found at volcanic sites. Now, J.F . McHone et al report its existence at the K-T boundary, at Raton, New Mexico. (McHone, John F., et al; "Stishovite at the CretaceousTertiary Boundary, Raton, New Mexico," Science, 243:1182, 1989.) A plus for the pro-impact side. The impact of an asteroid can initiate basaltic flooding and trap formation. Evidence of a global fire. Soot appears at the K-T boundary at many sites, but where did it come from? Chemical analyses of these soots show an enhanced concentration ...
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... Science Frontiers ONLINE No. 123: May-Jun 1999 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Moonstone In Orbit?A chunk of "something" about 50 meters across plays tag with the earth as it circles the sun. Discovered February 10, 1999 by an automated, asteroid-hunting telescope in New Mexico, the object's official name is 1999 CG9. Its orbit is nearly circular and 9 million kilometers farther away from the sun than the earth. Its year is 1.09 earth years. "The object's orbit is extremely unusual. Comets and asteroids that cross the earth's orbit normally have eccentric orbits. There is only one asteroid-like object, called 1991 VG, that has an similar orbit to that of earth. When it was discovered eight years ago, astronomers thought it might be a spacecraft that had escaped the earth's gravity." However, newly discovered 1999 CG9 is much too large to be a wayward piece of space hardware. The best guess is that it is a piece of the moon that was knocked off by an impacting asteroid. (Hecht, Jeff; "Chip off the Moon," New Scientist, p. 13, February 27, 1999.) Comment. Might it not be a chip off the earth itself? Or perhaps space hardware from somewhere else?! From Science Frontiers #123, MAY-JUN 1999 . 1999-2000 William R. Corliss ...
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... Science Frontiers ONLINE No. 67: Jan-Feb 1990 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Microorganisms complicate the k-t boundary Ancient bacteria, it appears, have tampered with the K-T (Cretaceous-Tertiary) boundary of some 65 million years ago. A key marker of this boundary is a thin "spike" of iridium that is found worldwide, and which was supposedly deposited by the asteroid impact that helped finish off the dinosaurs. For many scientists, the asteroid-impact scenario has become a "non-negotiable" brick in the Temple of Science. The problem they have faced is that the iridium layer is variable in thickness and concentration from site to site. Sometimes iridium can be detected well above and below the K-T boundary. This variability has tended to undermine the asteroid-impact theory. Recent experiments at Wheaton College by B.D . Dyer et al have demonstrated that bacteria in ground water can both concentrate and disperse iridium deposits. In other words, bacteria could smear out an iridium spike, perhaps partially erase it, or even move it to a deeper or shallower layer of sediment. (Monastersky, R.; "Microbes Complicate the K-T Mystery," Science News, 136: 341, 1989.) Comment. An obvious question now is how bacteria might have affected other chemicals, such as oxygen and carbon isotopes, widely used in stratigraphy. From Science Frontiers #67, JAN-FEB 1990 . 1990-2000 William R. Corliss ...
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... Science Frontiers ONLINE No. 98: Mar-Apr 1995 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects A Unified Theory Of Geophysics It takes a lot of nerve to propose a theory that can unite such a fragmented field as geophysics. H.R . Shaw makes a try in his new book: Craters, Cosmos, and Chronicles: A New Theory of the Earth . Shaw's ideas have recently been reviewed in Science News and our item is based on that article. Shaw contends that cosmic projectiles -- asteroids and comets -- have controlled almost all features of the earth's evolution. For example: Impacts have determined the positions of the continents. They have controlled the geomagnetic field. They have created volcanoes and massive basalt flows. They have caused mass extinctions. Of course, for two centuries, other catastrophists have proposed similar dire consequences of giant impacts. But Shaw does introduce three ideas that are worth recording here. Large impact craters occur in swaths. Although this has been suggested before, Shaw has mapped out several swaths where large craters of about the same age are located. His "K -T swath" includes the Chicxulub crater (Yucatan), the Manson crater (Iowa), the Avak crater (Alaska), and three more in Russia -- all of which were gouged out about the time of the Cretaceous-Tertiary (K -T ) boundary. Shaw has plotted several other swaths of different ages. The application of chaos theory to solar system debris. Shaw hypothesizes that ...
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... comet showers have created this regular pulse beat in the history of life. A recent issue of Science presents the results of an analysis of the ups and downs of 20,000 marine genera -- that is, percent extinctions over a period of 600 million years, as revealed by the fossil record. The graph of ten groups of 1000 genera shows at least two things: (1 ) strong hints of periodicity; and (2 ) suggestions that extinctions, whatever they really are, "cut across functional, physiological, and ecological lines." The plotters of these graphs, D. Raup and G. Boyajian, claim that whatever the mechanism, "major pulses of extinction result from geographically pervasive environmental disturbances." What besides powerful, external physical forces (read "comets and asteroids") could affect such wide ranges of marine organisms? (Lewin, Roger; "Pattern and Process in Extinctions," Science, 241:26, 1988.) Comment . This all sounds so reasonable that one must wonder why it is given space in Science Frontier. The reason is that we have a suspicion that it is all too easy, too simplistic. Could something more subtle be at work? After all, we really know next to nothing about the real workings of life-as-a -whole, its ups and downs. It is so easy to say that a group of organisms was done in by a temperature change or the fall of acid rain brought on by the impact of an asteroid. We always look for external forces, whereas the real ...
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... Science Frontiers ONLINE No. 68: Mar-Apr 1990 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Impact Delivery Of Early Oceans Where did the earth's oceans come from? For decades the stock answer has been: from the condensation of vapors escaping from the planet's cooling crust; that is, "outgassing." The possibility that some terrestrial water might have ar rived from extraterrestrial sources after the earth's formation has been discounted. The major reason behind this neglect was the expectation that the erosive effects of large-scale impacts of water-carrying comets and asteroids would preclude any net accumulation of volatiles, and could even reduce any existing inventories of surface water. C.F . Chyba has recently reexamined this question of cometary water influx vs. impact-caused water losses using the latest estimates of comet/asteroid fluxes during the period between 4.5 and 3.5 billion years ago, when bombardment of the inner solar system was thought to be especially severe. Rather than the expected net loss, Chyba computes that the earth would really have gained more than 0.2 - 0.7 ocean masses in that billion-year period. Venus would have fared equally well, but Mars, more sensitive to impact erosion, would have accreted "only" a layer of water 10-100 meters deep over the whole planet! (This Martian water is now mostly below the surface supposedly.) (Chyba, Christopher F.; "Impact Delivery and Erosion of Planetary Oceans in the Early ...
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... reversals and tektites "Nuclear winter" is a term now in vogue. And, believe it or not, the rains of tektites discussed below may have been the forerunners of climatic catastrophes similar to the postulated nuclear winters. We shall call them "meteor-impact winters. First, a tad of background: Great meteor impacts and tektite events seem to have occurred nearly simultaneously with deep-cutting biological extinctions and reversals of the earth's magnetic field. Ever since this apparent synchrony was recognized a few decades ago, theorists have been vying in generating scientific scenarios, especially some mechanism that would reverse the earth's magnetic field. New entrants in the lists are R. Muller and D. Morris, two Berkeley physicists. Here is how they see it: "A sufficiently large asteroid or cometary nucleus hitting the Earth lofts enough dust to set off something like a 'nuclear winter.' The cold persists long after the dust settles because of the increased reflectivity of the snow-covered continents. In the course of a few centuries, enough equatorial ocean water is transported to the polar ice caps to drop the sea level about 10 meters and thus reduce the moment of inertia of the solid outer reaches of the Earth (crust and mantle) by a part in a million. 'That doesn't sound like much, Morris told us. 'But when we realized that this translates into a full radian of slippage between mantle and core in just 500 years, we began to look seriously at the consequences.' With the moment of inertia of the crust and ...
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... Science Frontiers ONLINE No. 102: Nov-Dec 1995 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Huge fireball explosion in 1994 This remarkable event was mentioned by C. Keay in his review of D. Steel's book Rogue Asteroids and Doomsday Comets . It seems to have escaped or been ignored by the scientific press. We quote from Steel's book, in which he complains that such events get little publicity despite their ominous implications for the future of humanity. "It is therefore not surprising that the 10-meter-or-so asteroid that blew up over a largely vacant area of the western Pacific on February 1, 1994, producing an explosion equivalent to at least ten times that of the Hiroshima bomb (and possibly rather more), was not seen prior to impact. Surveillance satellites registered it as the brightest such explosion that they have picked up so far. Despite the efforts of numerous scientists in this area of study to make the military aware that such detonations do occur naturally, it appears that the U.S . President was awakened because the Pentagon thought that this incident might be a hostile nuclear explosion." From Science Frontiers #102 Nov-Dec 1995 . 1995-2000 William R. Corliss ...
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... Science Frontiers ONLINE No. 90: Nov-Dec 1993 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Alien Meteors Meteors or shooting stars are usually considered to be small fragments that have been broken off the asteroids plying orbits between Mars and Jupiter. If this belief is correct, meteors darting into the earth's upper atmosphere would have speeds less than 260,000 kilometers per hour. Any objects with significantly higher velocities must come outside the solar system. It has, therefore, been unsettling to find that quite a few meteors hit our atmosphere at speeds much higher than 260,000 km/hr. Radar measurements of 160,000 meteors by A. Taylor and colleagues, at a New Zealand site, found that about 1% (1500 meteors) struck the atmosphere with velocities greater than 350,000 km/hr. These speedsters must come from beyond the solar system. The question arising is: Whence all this interstellar debris? One hint comes from the fact that the aliens appear to come from the direction in which the sun and its family of planets are traveling through interstellar space. Evidently, this interstellar medium is far from a vacuum; it is strewn with flotsam and jetsam -- but from what smashed planets, moons, and asteroids? (Samson, Alan; "Radar Traps Visitors from Outer Space," Dominion Sun Times (Wellington), April 25, 1993. (Cr. P. Hassall) From Science Frontiers #90, NOV-DEC 1993 . 1993-2000 William R. ...
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... Science Frontiers ONLINE No. 107: Sep-Oct 1996 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects "NOT WITH A BANG BUT A WHIMPER"Poet T.S . Eliot speculated that life on earth might not after all be terminated catastrophically, as in the impact of a large asteroid (today's popular doomsday machine). Rather, we might depart slowly, quietly, and mournfully. Of course, Eliot was not thinking of asteroids -- no one foresaw impact havoc in his day. But, his use of the word "whimper" can be attached to another, much slower astronomical agent of planetary death: cosmic dust and gas. Here's the current situation: "For the most part of the past five million years, the Solar System has been moving through a rather empty region of interstellar space between the spiral arms of the Milky Way. But a few thousand years ago, it entered a diffuse shell of material expanding outward from an active star-forming region called the Scorpius-Centaurus Association. Such 'super-bubble' shells of gas and dust result from the formation of massive stars, or the explosion of those stars as they become supernovas, and contain gas and dust clouds of varying densities." The density of matter in this solarsystem-engulfing shell could well shroud our planetary system with dust and gas a million times more dense than that we now encounter. If this happens, the sun's rays would slowly dim and life forms dependent on photosynthesis would expire. ...
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... Science Frontiers ONLINE No. 28: Jul-Aug 1983 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Chiron: the black sheep of the solar system Charles Kowal discovered the smooth, very dark sphere called Chiron over five years ago. Only a little more is known about it today. Chiron is 300-400 kilometers in diameter -- asteroid-size. But its orbit (aphelion, 18.9 A.U .; perihelion, 8.5 A.U .) is definitely anomalous for asteroids. One would expect to find only comets in this region of the Solar System. To compound the mystery, Chiron's orbit is unstable. This planetoid was originally somewhere else (no one knows where) and was nudged into its present orbit by a major planet. One group of researchers calculates that Saturn could have been the nudger, and that the event might have happened as recently as 1664!! (Lipscomb, R.; "Chiron," Astronomy, 11:62, March 1983.) Comment. Only a minor bit of extrapolation will carry a proponent of catastrophism from a 1664 nudge of a 400-kilometer body to a much more violent Solar System rearrangement sometime during the past 10,000 years. From Science Frontiers #28, JUL-AUG 1983 . 1983-2000 William R. Corliss ...
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... 40 meters high have lost most of their dunes, leaving only raw, unweathered rock. On the other hand, the higher headlands have retained these dunes. Australians B. Young and T. Bryant hypothesize that a tsunamis 40 meters high swept the lower headlands clean about 100,000 years ago. They can even plot the incoming wave's direction, because a few remnants of the coastal dunes still cling to the southwest corners of the headlands along the NSW coast south of Newcastle. In their scenario, the tsunamis came from the northeast, smashed into the Solomons, southeastern Australia, and northeastern New Zealand. The Great Barrier Reef protected northeastern Australia from the full force of the wave. Young and Bryant favor a Hawaiian landslip as the initiator of the tsunamis, but acknowledge that an asteroid impact could also have done the job. If the wave began near Hawaii, it would initially been about 375 meters (about mile) in height. (Davidson, Garry; "A Tsunamis Tale from Sydney," New Scientist, p. 17, October 17, 1992.) 65,000,000 BP. Northeastern Mexico. The date mentioned is, of course, that of the Cretaceous-Tertiary boundary. This is the time when, many scientists believe, a very large asteroid slammed into northern Yucatan, forming the now-buried Chicxulub crater and wiping out the dinosaurs. Since the impact site was covered with ocean at the time, a powerful tsunamis should have surged out from this area. Indeed, debris attributable to a tsunami has been found on the U ...
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... North American Midwest. "Eight circular geologic structures ranging from about 3 to 17 km in diameter, showing evidence of outwarddirected deformation and intensive brecciation, lie within a linear swath stretching about 700 km across the United States from southern Illinois through Missouri to eastern Kansas. Based on their similar geological characteristics and the presence of diagnostic and/or probable evidence of shock, these structures, once classified as 'crypto volcanic' or 'cryptoexplosion' structures, are more confidently ascribed to hypervelocity impact. No other similar occurrence of aligned features is known, and we calculate the probability of a chance alignment to be less than 10- 9 ." The craters are all roughly the same age: 310-330 million years. Rampino and Volk suspect they were formed all at once by a string of asteroids or comets. (Rampino, Michael R., and Volk, Tyler; "Multiple Impact Event in the Paleozoic: Collision with a String of Comets or Asteroids?" Geophysical Research Letters, 23:49, 1996) Comment. We cataloged a possible chain of meteorite scars in Argentina, near Rio Cuarto, in SF#80. Linear chain of known and probable impact structures across the North American Midwest. From Science Frontiers #105, MAY-JUN 1996 . 1996-2000 William R. Corliss ...
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... Science Frontiers ONLINE No. 139: Jan-Feb 2002 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Tunguska: An Inside Job?Virtually all speculation about the 1908 Tunguska Event assumes an external cause: a meteor, a comet, an asteroid, or even the accidental explosion of an alien spaceship. A recent meeting of Tunguska experts in Russia looked down rather than up for Tunguska's initiating phenomenon. In this open-minded review, two little-publicized but highly pertinent Tunguska observations were discussed. The catastrophe had five centers of destruction rather than one. At the Tunguska site are many large root stumps, not yet rotted away, that cannot be linked to any pits associated with their origin. These stumps were apparently blown out of the ground and hurled dozens of meters from where they stood prior to the Event. Next to be considered were the unappreciated similarities between the Tunguska Event and the 1883 explosion of Krakatoa. The four bright nights in Europe and western Asia, straddling 30 June 1908, are remimiscent of the 1883 Krakatoa outburst, they ask for transient scatterers in the upper atmosphere, above 500 km, at heights which only methane and hydrogen are light enough to reach in sufficient quantity. Fast-rising natural gas has been repeatedly detected in recent years, in the form of "mystery clouds"---by airplane pilots---and indirectly as pockmarks on 6% of the sea floor. In other words, Tunguska might well have been---not an extraterrestrial impact--- ...
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... Science Frontiers ONLINE No. 62: Mar-Apr 1989 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects DANCING TO THE COMETS' TUNE "When planetary scientists examine one kind of meteorite rich in iron, the H-chondrites, they find that the meteorites' ages do not spread evenly through time. Instead, the ages seem to cluster at 7 and 30 million years." Astronomers have hitherto been content to attribute these clumped ages to collisions among the meteorites' parent bodies - the asteroids - which ply periodic orbits. However, S. Perlmutter and R.A . Muller, at Berkeley, point to the apparent 26- to 30-million-year periodicities of three terrestrial phenomena: Biological extinctions in the fossil record, Magnetic field reversals, and Terrestrial-crater ages. Could there be a connection between the clumped meteorite ages and these terrestrial phenomena? Perlmutter and Muller propose that all of these phenomena are the consequence of periodic storms of comets that invade the inner solar system from the direction of the Oort Cloud of comets that purportedly hovers at the fringe of the solar system. These comets not only devastate the earth but also collide with the asteroids, knocking off those bits and pieces we call meteorites. (Anonymous; "Do Meteorite Ages Tell of Comet Storms?" Astronomy, 17:12, January 1989.) Comment. Unanswered above is the question of why comet storms should be periodic. One hypothesis is that Nemesis, the so-called Death Star, a dark companion of our sun, lurks ...
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... Science Frontiers ONLINE No. 113: Sep-Oct 1997 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects An exploded planet and the "face on mars"Between Mars and Jupiter swirls the main main asteroid belt. In the view of many astronomers, including T. Van Flandern, there resides the debris of an exploded planet. Van Flandern has adduced considerable evidence supporting the exploded planet hypothesis, which we will pass over in favor of a look at the possible effects of said exploding planet upon a large but equally hypothetical satellite of said planet. Such a satellite would have been heavily pelted by debris on the side facing the exploding planet. Furthermore, this battered sphere, having lost its gravitational "anchor," would assume a new orbit around the sun as well as a new orientation in space. Is there any object in the solar system plastered mainly on one side with debris and craters? You guessed it: Mars! What possible connection could there be between this purported cataclysm and the "face on Mars"? The connecting thread is very weak but so beguiling that we must mention it. T. Van Flandern has proposed eight tests for the artificiality of the "face" and its associated "pyramids," "city," etc. One is the three-dimensionality of the "face." Another is the "fractal" test, which is useful in distinguishing between artificiality and naturalness. The "face" readily passes four of the eight tests. A fifth test (bilateral symmetry) cannot be decided ...
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... Science Frontiers ONLINE No. 60: Nov-Dec 1988 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Global fire at the k-t boundary The worldwide deposit of iridium at the K-T (Cretaceous-Tertiary) boundary has been considered very strong evidence that a large astronomical object (asteroid or comet) devastated our planet some 65 million years ago. Some scientists, however, propose that the iridium layer was instead deposited through widespread volcanic activity. The proponents of an astronomical mechanism should be heartened by a recent paper in Nature, by W.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 ...
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... Science Frontiers ONLINE No. 60: Nov-Dec 1988 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Collision/eruption/extinction/ magnetic reversal An increasingly popular scenario is: (1 ) Every 34 million years the solar system bobs up and down through the thickly populated disk of our galaxy; (2 ) The resulting encounters lead to showers of comets and/or asteroids on earth; (3 ) The mechanic trauma leads to basalt flooding; (4 ) Great biological extinctions occur in consequence; and (5 ) The terrestrial magnetic field reverses in step. Now, if scientists could show that all of these phenomena occur at the same frequency and are roughly in phase, it would constitute one of science's most important syntheses. The stratigraphic record and the estimated ages of meteor craters certainly hint at such synchrony. Recently, two more papers have appeared which support the above scenario. First, M.R . Rampino and R.B . Stothers show that during the past 250 million years, eleven episodes of basalt flooding have occurred with an average cycle time of 32 million years. Second, J. Negi maintains that the earth's magnetic record boasts a similar string of disturbances, with an average period of 33 million years. (Anonymous; "Regular Reversals in Earth's Magnetic Field A Fluke?" New Scientist, p. 32, August 25, 1988.) From Science Frontiers #60, NOV-DEC 1988 . 1988-2000 William R. Corliss ...
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... Science Frontiers ONLINE No. 87: May-Jun 1993 Other pages Home Page Science Frontiers Online All Issues Last Issue Next Issue Sourcebook Project Sourcebook Subjects Contents Archaeology The 50,000-year-old americans of pedra furada The zuni enigma The american discovery of europe! Astronomy The earth: a doubly charmed planet Cosmic soot and organic asteroids Biology Fossil feathers fly Is caddy a mammal? The uniqueness of human adolescence Animals attack human technological infrastructure Late survival of mammoths Geology Whence the earth's pulse? Giant impact-wave deposit along u.s . east coast Geophysics The vent glow and "blind" shrimp Amazons in the sky The bottle-green icebergs of antarctica Psychology Alien abuctions: were they, are they real? Calculating prodigies, gnats, and smart weapons ...
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... Science Frontiers ONLINE No. 37: Jan-Feb 1985 Other pages Home Page Science Frontiers Online All Issues Last Issue Next Issue Sourcebook Project Sourcebook Subjects Contents Archaeology A Disaster-driven Early Civilization Another Remarkable Specimen of Ancient Man Astronomy The Puzzle of the Moon's Origin When Mars Had Lakes Why Aren't the Martian Craters Worn Down? Flip-flop Radio Jets? Biology The Genome's Responses to Challenges "hopeful Monsters" in Iceland? Parasites May Reprogram Host's Cell Geology More Doubts About Asteroids The Earth is Expanding and We Don't Know Why The Grand Canyon Conundrum Evidence for A Giant Pleistocene Sea Wave Recent Pulsations of Life Geophysics "Crystal" Ball Lightning The Big Divot! Shower of Coke Chemistry & Physics Squarks and Photinos At Cern? What Does it All Mean? The Secret of it All is in the Pi ...
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... Science Frontiers ONLINE No. 36: Nov-Dec 1984 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects The Case Against Impact Extinctions The neocatastrophists seem to be getting overly smug with their iridium-rich deposits at the Cretaceous-Tertiary boundary. Is there really incontrovertible evidence that a large asteroid or comet hit the earth at this point in history, causing widespread biological extinctions? To add some perspective, Leigh M. Van Valen has tossed 15 arguments against impact extinctions on the scales. Ten of these are reproduced below, as taken from Nature. More de-tails may be found in Paleobiology, 10: 121, 1984. Freshwater life was unaffected; In Montana and its vicinity, the last occurrence of dinosaurs was detectably below the crucial boundary; Transitional floras also exist below the boundary; Apparently extraterrestrial material exists below the boundary; The expected effects of eliminating atmospheric ozone are missing; The Cretaceous-Tertiary boundary is coincident with a very large marine regression, suggesting a nonextraterrestrial cause; Marsupials but not placentals were nearly eliminated, while most aboreal multituberculates (a type of vertebrate) and birds survived; The predicted cooling effects on the earth are absent; The predicted effects of acid rain cannot be found; and Assuming a marine impact, no turbidites can be found; assuming a land impact, no large terrestrial crater has been discovered. (Van Valen, Leigh M.; "The Case against Impact Extinctions," Nature, 311:17, 1984.) From Science Frontiers #36, NOV-DEC 1984 . ...
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... Science Frontiers ONLINE No. 86: Mar-Apr 1993 Other pages Home Page Science Frontiers Online All Issues Last Issue Next Issue Sourcebook Project Sourcebook Subjects Contents Archaeology The acoustics of rock art Where did agriculture really begin? Astronomy Meteoric "dust bunnies" Cosmic snowballs and magnetic asteroids Biology Must we die? the medfly's answer How a fly hears what a cricket hears Once more science fiction predicts the future! Rethinking aids Geology Geysers as detectors of distant earthquakes Precariously balanced rocks as earthquake detectors Geophysics An electrical virtuoso The milky sea a.k .a . "white water" A CURIOUS SIGHTING Cloud plumes natural but still a bit anomalous Logic and Mathematics Math's mystery All roads lead to 123 Psychology Hypnosis and skin temperature Hypnosis and basketball Physics Solar radiation and mental illness ...
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... . Similar but much smaller "microtektites" appear in deapsea de posits in the adjacent oceans. Radiometric and fission-track dating indicate that the tektites solidified about 700,000 years ago. Yet, their geological age, as measured by the age of the terrestrial sediments in which they are found, is only a few thousand years. This great disparity in age engendered a confrontation between geologists and geophysicists. The latter insisted on their 700,000-year figure; the former said "maybe so" but the tektites are still found only in very young, superficial sediments. The point here is that time-of-solidification may not be the same as time-of-fall. At stake is the prevailing theory, now dogmatically proclaimed, that tektites are created when a large asteroid impacts the earth, ejecting molten droplets of rock which shower back to earth as solidified tektites. No one has ever found a suitably large crater ( 200 miles in diameter) assignable to the Australasian tektite strewn field. Nevertheless, the impact model prevails; and the young geological age of the tektites is dismissed as erroneous. A Soviet scientist, E.P . Izokh, has recently proposed a radically different scenario that would produce both the young and old dates. If a moon, or Jupiter, or some similar body, explosively ejected the glassy tektites, embedded in an icy cometary body some 700,000 years ago, the tektites could, after cruising through space for millenia, have fallen to earth recently and over a wide area. Thus, both geologists and geophysicists would be ...
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... Science Frontiers ONLINE No. 95: Sep-Oct 1994 Other pages Home Page Science Frontiers Online All Issues Last Issue Next Issue Sourcebook Project Sourcebook Subjects Contents Archaeology Blondes in ancient china Evidence of tobacco in ancient egypt Dwarf mammoths in ancient egypt? Astronomy "AN UNPRECEDENTED AND BIZARRE OBJECT" Comets, asteroids, or neither? This was the big one, but where did it come from? Snowballs in hell? Biology It's according to hoyle and wickramasinghe Music of the hemispheres The urge to replicate: part i The urge to replicate: part ii Geology Might diamonds be dead bacteria? Deep quake deepens mystery Geophysics Sylvanshine: a newly recognized optical phenomenon Gamma-ray flashes in the upper atmosphere A DEEP-SEA HYDROTHERMAL VENT INSTEAD OF A WARM LITTLE POND? Psychology The solar wind and hallucinations Physics Cold fusion update: 1994 Miscellaneous A SKEPTIC'S NDE -- NOT SO MYSTICAL ...
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... Science Frontiers ONLINE No. 68: Mar-Apr 1990 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects New Life For Martian Life After the negative (some say "ambiguous") results from the Viking spacecraft life-detection experiments in 1976, astronomers and biologists have proclaimed that Mars is sterile. This pronouncement may have been premature. A meteorite discovered in Antarctica in 1979 may change a few minds on this matter. This particular meteorite is one of the handful thought to have been blasted off into space by an oblique impact of an asteroid on the surface of Mars. Somehow, statistics were kind to these tiny Martian orphans, for they found their ways to the Antarctic snows. But what is really exciting is the recent discovery that chemical analysis of one of these purported Martian meteorites revealed a high concentration of organic material deep within. The implication is that Martian life existed, perhaps still does exist, beneath the Martian surface, where the Viking Lander's scoop could not get at it. (Anonymous; "Life under Mars?" Sky and Telescope, 78:461, 1989.) Comment. In other words, Mars like the earth, may harbor an unappreciated fauna in crevicular structure beneath the environmentally rigorous surface. See also: SF#67. From Science Frontiers #68, MAR-APR 1990 . 1990-2000 William R. Corliss ...
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... Science Frontiers ONLINE No. 5: November 1978 Other pages Home Page Science Frontiers Online All Issues Last Issue Next Issue Sourcebook Project Sourcebook Subjects Contents Archaeology How Ancient is Vermont? Early Man in Australia Even Earlier A 6,000-year-old Structure in Scotland Astronomy A Redshift Undermines the Dogma of An Expanding Universe Asteroids with Moons? Cometary Appearance of Venus Nine-tenths of the Universe is Unseen Petrol Channels on Mars? Biology Fish Creates Fish The Obscure Origin of Insects and Their Wings Sunspots and Flu Geology Halos and Unknown Natural Radioactivity Geophysics 70th Anniversary of the Tunguska Event Bioluminescent Patch Detected by Radar The So-called Green Fireballs of 1948-1949 Psychology Fire-walking: Anyone Can Do It ...
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... Science Frontiers ONLINE No. 102: Nov-Dec 1995 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects A TUNGUSKA-LIKE BLAST IN BRAZIL IN 1930 In a review of D. Steel's new book Rogue Asteroids and Doomsday Comets , C. Keay injects a startling bit of news: "Too late for Duncan Steel to include before his book went to press, comes the latest news that British astronomer Mark Bailey and his colleagues have discovered that a Tunguska-like event in 1930 blasted flat a huge expanse of jungle near an upper tributary of the Amazon in Brazil close to the border with Peru. The resulting fires burned for months. The only European near at hand was a Catholic priest, whose reports of the incident have lain unnoticed in the Vatican library until now." (Keay, Colin; "The NonDenominational Day of Reckoning," The Skeptic, 15:44, Spring 1995. This journal is published in Australia and should not be confused with the UK journal of the same name.) From Science Frontiers #102 Nov-Dec 1995 . 1995-2000 William R. Corliss ...
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... Science Frontiers ONLINE No. 104: Mar-Apr 1996 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects An Antarctic Bone Bed W. Zinsmeister was accustomed to scoff at the idea that the Age of Dinosaurs ended violently with the impact of a giant asteroid some 65 million years ago. He always asked: "Where's the layer of burnt and twisted dinosaur bones?" His certainty was shaken, however, when he began mapping fossil deposits on Seymour Island, Antarctica. He didn't find the dinosaur bones but rather a giant bed of fish bones at least 50 square kilometers in area. Some sort of catastrophe must have annihilated untold millions of fish. And guess what? This great bone bed was deposited directly on top of that layer of extraterrestrial iridium that marks the 65-million-year-old Cretaceous Tertiary boundary at many sites around the world. (Hecht, Jeff; "The Island Where the Fish Had Their Chips," New Scientist, p. 16, November 11, 1995) Cross reference. Bone beds of fish and other creatures are filed under ESB13X2 in Anomalies in Geology. To order this catalog, see here . From Science Frontiers #104, MAR-APR 1996 . 1996-2000 William R. Corliss ...
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... Science Frontiers ONLINE No. 10: Spring 1980 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Cosmic Death Waves In the language of science, W.M . Napier and S.V .M Clube provide a scenario of cyclic terrestrial catastrophism. Their thesis is that the solar system periodically passes through the regularly spaced spiral galaxy arms every few 107 years. Planetesimals in these arms cra-ter the solar-system planets at these times and also provide the raw materials for new comets, asteroids, satellites, and even planets. Supporting their theory is the repeating history of geological revolutions with the accompanying extinctions and reflowerings of life. A remarkable feature of this paper is a table of shortlived solar-system phenomena (comets and rapidly evolving staellite-and-ring systems). The tenor is one of episodic catastrophism and a rapidly changing solar system; viz., Saturn's rings evolving in only 104 years. (Napier, W.M ., and Clube, S.V .M .; "A Theory of Terrestrial Catastrophism," Nature, 282:455, 1979.) Comment. This outlook differs radically from that still disbursed in our schools and colleges. From Science Frontiers #10, Spring 1980 . 1980-2000 William R. Corliss ...
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... Science Frontiers ONLINE No. 59: Sep-Oct 1988 Other pages Home Page Science Frontiers Online All Issues Last Issue Next Issue Sourcebook Project Sourcebook Subjects Contents Archaeology Stele with Unknown Glyphs Found Near Vera Cruz All Roads Lead to Chaco Canyon How and When the Americas Were Peopled Astronomy "? " ! ? Nereid: Grotesque Shape Or Two-faced? Memoirs of A Dissident Scientist Biology Nothing Reacts with Something? Periodic Extinctions and Explosions in Terrestrial Life Aids: Another Great Deceiver Geology Going for Gold Is There Truth in the Grains? Did An Asteroid Impact Trigger the Ice Ages? The New Archaeoperyx Fossil Geophysics Fish and Winkle Showers Lightningless Thunder? Psychology The Enigma of Multiple Personality Observations of Luminous Phenomena Around the Human Body ...
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... Science Frontiers ONLINE No. 93: May-Jun 1994 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects From Dust Unto Dust This Biblical assertion may be right on the mark, but in a sense that is slightly different from what is usually meant. The "first" dust may not have been terrestrial dust but interplanetary dust. Let us commence with long-winged U2s cruising at 20 kilometers altitude or more. Collectors coated with silicone oil are deployed. To them stick tiny bits of interplanetary and interstellar debris that have been caught by earth's gravity and are slowly drifting downward in the atmospshere. Some of these micron-sized particles come from asteroid collisions; others from the disintegration of comets. This rain of cosmic matter is not negligible; the earth harvests about 40,000 tons annually from the fertile fields of outer space. "Fertile?" Yes, outer space is a vast biochemical retort. D. Brownlee, R. Walker, and others: ". .. suggest that interplanetary dust has probably carried organic matter to Earth since the early aeons of the solar system. The complexity of the organic molecules found on these particles has fueled the imaginations of many who ponder the role extraterrestrial matter may have played in the prebiological evolution of organic material on the primordial Earth." Beyond these conjectures, several other things about interplanetary dust particles bother scientists: "' What is surprising,' Walker notes, 'and still not understood, is the fact that the organic molecules we see in the dust particles are ...
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... Sourcebook Subjects Gaia as a super-superorganism The Gaia hypothesis states that the earth's environment is maintained suitable for life by life itself. Our climate, atmospheric oxygen level, ocean composition, and similar vital conditions are kept livable by life's waste products, such as the oxygen emissions of plants. That something like Gaia is required is seen in the extreme disequilibrium of the earth's atmosphere compared to the near-equilibrium of the atmospheres of apparently lifeless Venus and Mars. For example, our atmosphere's 21% oxygen, a highly reactive gas, is many orders of magnitude higher than one would expect on a lifeless planet. Furthermore, life-friendly conditions have been maintained for billions of years despite large changes in the sun's output and the traumas of asteroid impacts. T.M . Lenton, writing in Nature, asks a salient question: How has planetary self-regulation (Gaia) been established and maintained by evolution and natural selection which operate on the level of individuals? In other words, evolution tells us that organisms should evolve so as to leave the most progeny not so as to regulate the atmosphere. Lenton answers that there must be feedback loops from the planetary environment that steer the evolution of individuals in the "proper" direction. Lenton goes on to explore some of these many feedback mechanisms; one obscure loop involves the production of dimethyl sulfide by marine phytoplankton. Truly, it is a tangled bank! All of the feedback loops imply that the evolution of life forms is constrained (or dictated) by the need to ...
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... Science Frontiers ONLINE No. 26: Mar-Apr 1983 Other pages Home Page Science Frontiers Online All Issues Last Issue Next Issue Sourcebook Project Sourcebook Subjects Contents Archaeology A Mysterious Copy of the Grave Creek Stone Archeology in Britain: Straying From the Party Line Astronomy Gyroscopic Galaxies Antarctic Meteorite May Have Been Blasted Off the Moon Biology Lizardless Thrashing Tails Nature's Ballistic Missile Prescient Evolution Geology Do the Continents Really Drift? Punching A Hole in the Asteroid Hypothesis Geophysics Slithering Patch of Light Earthquake and Subterranean Fire Psychology Everyone A Memory Prodigy The Mind's Rhythm Chemistry & Physics Maybe There's One Stable Particle! ...
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