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Electric fields are produced by clouds, fog, rain, sleet, snow, tornadoes, dust devils, volcanoes, earthquakes, meteors, and contaminants in air. On mountains, electrical activity often becomes intense. Experienced climbers can tell bizarre stories of mountaintop electricity. Researchers themselves have often been astonished at nature's complexity. Ball lightning, for example, although witnessed and reported many times in the past, has only with difficulty been established as a genuine scientific problem. Years of patient effort were required to distinguish ball lightning from retinal afterimages and optical illusions. In view of the numerous manifestations of atmospheric electricity, it is reasonable to try to determine whether or not some luminescent UFOs are indicative of yet another electrical phenomenon of nature.
Much research has been done theoretically, in the laboratory, and in the field that bears on the problems of atmospheric electricity and the plasma state of matter. Here we emphasize the more unusual (and often speculative) aspects of these subjects and their possible correlation with descriptions of UFO behavior. People who have witnessed unusual electrical phenomena of the types reviewed
in this chapter are invited to send reports to
Dr. Bernard Vonnegut
Earth Science Building, Room 323
State University of New York at Albany
1400 Washington Avenue
Albany, New York 12203
or phone them to 518-457-4607 or 518-457-3898.
The author thanks Drs. Sydney Chapman, John Firor, Sadami Matsushita, and J. Doyne Sartor of the National Center for Atmospheric Research, and Professor Julius London of the Department of Astrogeophysics, University of Colorado, for reviewing portions of this manuscript, for informative and pleasant discussions, and for useful references. He is also indebted to Dr. Edmond M. Dewan of the Air Force Cambridge Research Laboratories for a file of useful reprints.
In its lowest energy state, an atom contains an equal number of electrons and protons, and is electrically neutral. By gaining or losing electrons, an atom or molecule can acquire an electric charge. A charged atom or molecule is called an ion. If some of the atoms of a gas become ions, the gas is said to be partially-ionized. When there are enough ions or electrons to affect the physical properties of the gas, the gas is called a plasma. The "plasma state of matter" refers to an ionized medium.
An atom may become ionized by
In processes (a) and (b), atoms lose one or more electrons and become positive ions. In process (c), atoms gain an electron and become negative ions. The ionization of the outermost layers of the atmosphere (above 65 km) is caused primarily by the absorption of solar ultraviolet radiation and x-radiation (process (a)). The weak ionization in the lower atmosphere is largely an effect of cosmic ray particles (mostly fast protons)
(process (b)). Free electrons in the lower atmosphere are quickly captured by oxygen molecules, which then become negative ions (process (c)).
When large electric fields are present, electrons and ions are accelerated to high velocities in short distances, and may acquire enough kinetic energy to ionize neutral atoms upon collision. The new charges are accelerated in turn by the electric field, collide with still other neutral atoms, and produce more electrons and ions. The ionization of a neutral gas by the acceleration of a few electrons and ions in a large electric field is called an avalanche process. The avalanche process is responsible for coronal point discharge (St. Elmo's fire), lightning flashes, neon and fluorescent lighting, and Geiger counters.
Since electrons can be accelerated by high-frequency electric fields, ionization is sometimes possible in the presence of microwaves. High temperature shock waves surrounding meteors and reentering space vehicles also cause ionization in the atmosphere.
When a free electron and a positive ion collide, the electron may be captured. When a negative and a positive ion collide, an electron may be transferred from the negative to the positive ion. In such collisions, called recombination processes, ions are neutralized and become atoms or molecules. In the lower atmosphere, plasma (such as that created in a lightning flash) is rapidly neutralized through such processes. Radiation may be emitted during recombination.
Probably 99% of all the matter in the universe is in the plasma state. Within the stars, hydrogen, helium, and the other abundant atoms are completely ionized.
The visible surface of the sun, called the photosphere, is host to a mysterious plasma phenomenon, the sunspot. The strong
magnetic fields which emanate from sunspots interact with the plasma of the outer solar atmosphere. As a consequence, violent events, known as solar flares, are often generated in regions where the magnetic field gradient is large. During a solar flare, ions and electrons are accelerated out of the sun's atmosphere into interplanetary space. Some of these fast charged particles interact with the earth's magnetic environment, and contribute to short-wave radio blackouts, auroras (Northern and Southern Lights), and geomagnetic storms.
Basic plasma research is vital in many technological areas. In the field of communication, problems arise in connection with radio and radar transmission through plasma regions such as the ionosphere and the ionized sheath surrounding re-entering spacecraft. Laboratory efforts are under way to control the reactions of nuclear fusion for power generation. If successful, present experiments may lead to efficient sources of power which do not require fossil fuel or fissionable materials. In the field of space technology, engineers are developing low thrust ion rocket engines to propel the next generation of interplanetary spaceships.
The lower atmosphere (below 60 km) is not a plasma under normal conditions. In every cubic meter of air at sea level, the fair weather atmosphere contains roughly 3x1025 electrically neutral molecules and only about 5x108 ions. About 107 ion pairs are created per cubic meter every second by ionizing radiation, and a like number are neutralized by recombination processes. The lifetime of a light ion is several hundred seconds. When dust particles are present, light ions are rapidly absorbed, and long-lived heavy ions are created. Over land at ground level, gamma rays emitted by natural radioactive substances are the primary cause of atmospheric ionization. Above a few hundred meters over land, and everywhere over the oceans, cosmic
ray particles and secondaries are the major source of ionization. In the lower atmosphere (below 60 km) unattached electrons are immediately captured by oxygen molecules.
The presence of even a few ions in the lower atmosphere means that air is not a perfect insulator. An electric charge placed on a metal sphere which is insulated from the ground and suspended in air, will leak into the atmosphere; the higher the altitude of the sphere, the faster will be the leakage of electric charge.
Where air pollution is prevalent, the light ions are collected on heavy dust particles, creating heavy less-mobile ions. The electrical conductivity of polluted air is often ten times less than that of clean air.
The earth's atmosphere may be represented as a leaky dielectric medium bounded by electrically conducting layers (or equipotentials) at sea level and at about 60 km height. Sea level is taken as the zero reference or ground potential. The layer at 60 km, now called the electrosphere, is the lowest level in the atmosphere of uniform electrical potential. This article deals with the electrical effects that are possible in the lower atmosphere, where UFO's are reported.
At sea level in fair weather, there exists an average electric field of about 130 volt/m directed downward. The potential of the electrosphere is about 300,000 volts positive with respect to the earth's surface. The earth's surface contains over its entire area a net negative charge of 5x105 coulombs (or l0-9 coulomb/m2). An equal positive charge resides in the atmosphere above the ground. Because air is not a perfect insulator, an electric current of 1800 amp (or 3.6x10-12 amp/m2) flows downward (i.e. positive ions migrate downward, negative ions migrate upward). At higher altitudes, the current remains constant but the electric field decreases as the
electrical conductivity increases. At the height of commercial jet aircraft (12 km), the electrical potential of air has reached 90% of the potential of the electrosphere (i.e. about 270,000 volts).
This indicates that most of the positive charge resides in the troposphere in the form of positive ions.
With the values known for the electrical conductivity of air, the negative charge on the earth's surface should leak away in about five minutes. To maintain the negative charge on the earth's surface, and consequently the electric field of the lower atmosphere, a charging mechanism is needed which acts continuously.
Thunderstorms maintain the fair weather electrostatic field. Every hour, several hundred thousand lightning flashes and coronal point discharges transfer negative charge from the bases of thunderclouds to the ground. The average charge transmitted by a lightning flash is estimated to be about 20 coulombs. Positive ions also rise from the tops of thunderclouds.
Many theories have been proposed to explain how negative and positive charges are separated in a thundercloud. The mechanism must (1) give a positive charge to the upper part of the cloud and a negative charge to the lower part of the cloud, (2) provide a charge separation rate of several amperes.
It is generally believed that as precipitation particles fall they acquire negative charge. Consequently, negative charge is carried to the bottom of the cloud. A detailed understanding of the mechanisms involved in transferring charge between precipitation particles (and air pollutants) is of major scientific importance.
Strong evidence that thunderclouds act as batteries for the atmosphere is provided by the daily fluctuations in the fair weather
electric field. Over the oceans the fair weather electric field fluctuates 15 to 20% about its mean value, and reaches a maximum at 1900 Greenwich Mean Time everywhere over the earth regardless of the local time. Smaller secondary maxima occur at 1500 GMT and at 0700 GMT. Much of the earth's thunderstorm activity occurs in tropical regions during mid-afternoon when surface heating is most apt to produce strong convection. At 1900 GMT, it is mid-afternoon in the Amazon basin; at 1500 GMT, it is mid-afternoon in Africa; at 0700 GMT, it is mid-afternoon in Indonesia. The minimum fair weather field occurs at 0300 GMT when it is mid-afternoon in the middle of the Pacific Ocean.
If each thunderstorm supplies a charging current of 1 amp, there must be at least 1800 thunderstorms raging simultaneously over the earth at any one time to maintain the fair weather electric field. This is not an unreasonable estimate. It seems probable, therefore, that thunderstorms are the prime cause of the earth's electrical activity.
Current surges in the atmosphere are known as lightning. Lightning limits the magnitude of the electrical dipole of a thundercloud. Only about 20% of all lightning flashes are between cloud and ground. The majority of flashes occur within clouds. Here we briefly describe only the cloud-to-ground event, for which better information is available.
What appears to the eye as a single lightning flash is actually a number of individual charge surges, called strokes, recurring in rapid succession. A flash consists of between one and forty main strokes, each of which is preceded by a leader stroke. The median number of strokes in a lightning flash is about three.
When electric field strengths build up to values of about 3x106 volt/m near the edge of a cloud, avalanche processes become important. The visible lightning event begins with the initiation of a stepped leader from the cloud region where the electric field is most intense. The stepped leader is a conducting channel, perhaps a few centimeters in diameter, which is at essentially the same potential as the base of the cloud. Consequently, as the leader progresses downward away from the cloud, the electric field (i.e. the potential gradient) between the tip of the leader and the surrounding air continually increases, so that further ionization becomes easier.
After advancing about 20 meters (the exact distance depending on the field strength), the leader pauses for about 50 microseconds, forges ahead another 20 meters, stops again, and so on. (It is believed that the ionization of the air immediately ahead of the stepped leader is initiated by an avalanche region called a pilot streamer.) The stepped leader advances downward toward the ground along a zigzag path roughly parallel to the electric field. After about 100 steps and 50 milliseconds, the stepped leader has almost traversed the 2 km or so between the cloud base and the ground. When the stepped leader descends to about 20 meters altitude, it is met by a positive streamer from the earth. (The potential difference between the cloud and the ground may reach 108 or 109 volts before a lightning flash).
As soon as the conducting channel between the cloud and the ground is completed, the main (or return) stroke begins. In less than 10 microseconds, a current of about 20,000 amp is forcing its way through a conducting channel only a few millimeters in diameter. (The maximum current ever recorded in a lightning flash was 345,000 amp.) On the average, about 109 joules (an energy equivalent to 1/4 ton of TNT) are released in the flash event.
The temperature in the lightning channel, measured spectroscopically, reaches 30,000°K only 12 microseconds after the passage of the tip of the return stroke, but decays so rapidly that it falls to 5,000°K in about
50 microseconds. If thermalization is achieved, these temperatures are hot enough to cause considerable dissociation and ionization of air molecules. Some scientists argue, however, that thermal temperatures never exceed a few thousand degrees Kelvin. The precise time variation of the thermal temperature is important in estimating lightning damage by acoustic shocks.
Magnetic field strengths associated with lightning are in the neighborhood of 1 tesla (=104 gauss), so that the plasma pinch effect is probably of importance. Possible magnetic effects of a lightning stroke have been considered in connection with ball and bead lightning.
After the first leader and return stroke, the lightning flash may continue with another current surge along the same conducting channel. This second stroke is initiated by a dart leader, which advances continuously (not in steps) and more rapidly than the stepped leader. The dart leader follows the main channel to the ground and ignores the ungrounded branch channels of the first stroke. When the dart leader reaches the ground, a return stroke follows.
Recombination processes work rapidly in the atmosphere. Only 100 milliseconds after the cessation of a return stroke, the lightning channel is no longer sufficiently conducting to guide a dart leader. The lightning flash is then completed. Another stroke from the same part of a cloud must follow a completely new path, one created by a new stepped leader. For this reason, reports of ball lightning lasting as long as a few seconds were discounted or considered to be afterimages of the eye. There is still no satisfactory explanation for long-lived isolated electrical luminescence in the atmosphere.
Among the most mysterious manifestations of atmospheric electricity is the phenomenon of ball lightning or Kugelblitz. A glowing ball either
Collisions with aircraft have caused verified damage, indicating that ball lightning is not restricted to ground level.
Most witnesses report that ball lightning is clearly visible in daylight although not as bright as an ordinary lightning flash. Some 85% of the observers agree that the size and brightness of the ball remains roughly constant throughout the period of observation and that no changes occur even immediately prior to its disappearance. A minority report brightening and color changes just before the ball vanishes. The colors red, orange, and yellow are most common, but most other colors are seen occasionally. Some researchers believe that blue or blue-white Kugelblitz is associated with higher energy, although there is no statistical basis for such an assertion. The reported diameters of Kugelblitz range between 5 and 80 cm with a median of about 30 cm. One survey lists three complexions of ball lightning:
The last type seems most common. About 1/3 of the witnesses detect internal motions or rotation of the ball itself, although this may depend on the distance of the observer.
A majority of onlookers report the motion of the ball to be slow (about 2 meters/sec.) and horizontal, with no apparent guidance by the wind or by the ground. One in six observers report speeds in excess of 25 m/sec. Several reports do indicate some guidance from telephone or power lines and by grounded objects. An odor of brimstone (burning sulfur) is often reported by nearby observers, especially at the time of decay.
The median lifetime of ball lightning is roughly four seconds, with 10% reporting over 30 seconds. Determination of lifetime is difficult because
In any case, since an ordinary lightning channel can remain electrically conducting for only 0.1 second, a 10 second lifetime is two orders of magnitude beyond expectation.
Not long ago, considerable scientific discussion ensued on the question of whether ball lightning is a real phenomenon. Scientists believed that ball lightning could be
Today most researchers believe that Kugelblitz is a genuine electrical effect. A recent survey indicates that ball lightning may be extremely commonplace, but that the observer must be relatively close to the ball to be able to see it. Kugelblitz is probably invisible or indistinguishable in daylight at distances greater than 40 meters, which would explain why it is incorrectly believed to be a rare phenomenon.
The median distance between an observer outdoors and ball lightning is 30 meters. Sometimes ball lightning floats through buildings. The median distance between indoor observers and ball lightning is only 3 meters. The reported distance of the observer seems to be closely correlated with the reported size of the ball. A more distant observer is
The second difficulty is somewhat mitigated since in most cases of ball lightning terrestrial landmarks can be used for reference in estimating distances and sizes. On the other hand, estimates of the distance and size of a luminous sphere seen against the sky can be quite inaccurate.
In one report, a red lightning ball the size of a large orange fell into a rain barrel which contained about 18 liters of water. The water boiled for a few minutes and was too hot to touch even after 20 minutes. Assuming
one needs roughly 8x106 joules of energy (equivalent to 2 kg of TNT). For a ball 10 cm in diameter (the size of a large orange), the energy density is then 5x109 joule/m3. But if all the air in a volume were singly-ionized, the energy density would be only 1.6x108 joule/m3. Both the energy content and the energy density of ball lightning as derived from the singular rain barrel observation seem incompatible with the non-explosive character of most Kugelblitz. Although many lightning balls emit a loud explosive (or implosive) noise upon decay, effects characteristic of the release of energies of the order of 2 kg of TNT have rarely been reported (understandably if the observer was within 3 meters) . Moreover, explosive or implosive decays have been noted indoors with no apparent heat or damage to nearby ceramic objects. Nevertheless, there are enough well-documented cases of extremely high energy Kugelblitz to make the water barrel report very believable. Probably there is a wide range of possible energies for a lightning ball, with the vast majority of Kugelblitz possessing energy densities less than that of singly-ionized air. The minimum possible energy of a lightning ball is that required to illumine a sphere about 25 cm in diameter with the brightness of a fluorescent lamp. With 10% efficiency, this means a source of 250 watts for 4 sec., or about 1000 joules of energy. We can only conclude with certainty that the energy of a lightning ball lies somewhere between 103 and 107 joules.
Theoretical efforts have focused on the energy estimate of the rain barrel observation. To maintain a fully-ionized, perhaps doubly-ionized mass of air requires either
Theories which attempt to bottle fully-ionized plasma by magnetic fields or magnetovortex rings are faced with severe stability problems. There is no known way to contain plasma in the atmosphere for as long
as a few seconds. Moreover, a fully-ionized plasma ball would be hotter and probably less dense than the surrounding air, so that it would tend to rise rather than descend or move horizontally. Chemical combustion theories cannot explain the high energy content or the remarkable antics of the ball. Nuclear reactions would require an electric potential of at least 106 volts between the center and surface of the ball, and a mean free path for the ions as long as the potential gap. This situation seems unlikely, and faces similar problems of stability.
Theories which depend on an outside source of energy such as microwaves or concentrated d-c fields cannot explain how ball lightning can survive indoors.
If energies as high as several megajoules are not required, we can try other hypotheses. One suggestion is that the lightning ball is a miniature thundercloud of dust particles, with a very efficient charge separation process. Continuous low energy lightning flashes are illuminating the cloud. Another idea is that a small amount of hydrocarbon, less than that required for combustion, is suddenly subjected to strong electric fields. The hydrocarbons become ionized and form more complex hydrocarbon molecules which clump together. Eventually there is enough combustible material in the center to allow a burning core. If the concentration of hydrocarbon decreases, the ball disappears if the concentration increases, the ball ignites explosively. (This represents the swamp gas theory for ball lightning).
Much depends on a reliable energy estimate for the Kugelblitz. If the energy is as high as indicated by the water barrel report, we have a real dilemma. At present no mechanism has been proposed for Kugelblitz which can successfully explain all the different types of reports. Probably several completely different processes can produce luminescent spheres in the atmosphere.
We conclude this section with summaries of several eyewitness reports of Kugelblitz.
The first few cases concern aircraft.
He considers smaller luminous balls seen near his aircraft to be St. Elmo's fire. If Kugelblitz within clouds can be as large as is estimated by this pilot, then ground-based observations reflect only weak manifestations of the phenomenon.
The following case is indicative of high-energy ball lightning.
Cases like these are not unusual. Ball lightning has been known to cut wires and cables, to kill or burn animals and people, to set fire to beds and barns, to chase people, to explode in chimneys, and to ooze through keyholes and cracks in the floor. It has even been reported in the passenger compartment of a DC-3 aircraft. Moreover, lightning conductors are not always able to dissipate the energy of Kugelblitz. In St. Petersburg, Fla., during the summer of 1951 an elderly woman was found burned to death in an armchair near an open window. Above one meter, there were indications of intense heat - melted candles, cracked mirror, etc. A temperature of 1400°C would have been needed to produce such effects. But below one meter there was only one small burned spot on the rug and the melted plastic cover of an electric outlet. A fuse had blown, stopping a clock in the early morning hours. Since lightning is common near St. Petersburg, this case has all the marks of Kugelblitz.
A sharp point which extends from a charged conducting surface is a region of maximum electric field. During a thunderstorm, therefore, we can expect large electric fields near trees, towers, tall buildings, the masts of sailing ships, and all other points rising from the earth's conducting surface.
If the electric field becomes large enough, avalanche processes can cause electrical breakdown of the surrounding air and a sustained coronal discharge. Coronal effects may transfer more charge between
cloud and ground than does lightning.
St. Elmo's fire appears as a glowing luminescence hovering above a pointed object or near a wire conductor. It is usually oval or ball-shaped, between 10 and 40 cm in diameter, and has a glowing blue-white appearance. Its lifetime exceeds that of ball lightning, sometimes lasting several minutes. The decay is silent but may be sudden or slow. Sometimes hissing or buzzing noises can be detected.
The primary difference between ball lightning and St. Elmo's fire is that St. Elmo's fire remains near a conductor. It has been observed to move along wires and aircraft surfaces, sometimes pulsating. Foo-fighters are probably a manifestation of St. Elmo's fire. Eyewitness reports of coronal discharge are presented in Section 14. Here is an account of St. Elmo's fire from the same pilot who gave observation 3 of the previous section.
"The smaller 'ball lightning' I have always associated as being the phenomenon known as St. Elmo's fire; however, St. Elmo's fire generally consists of an infrequent blanket covering the leading edges and trailing edges of an aircraft. It does not blind or brighten but is merely irritating as it prevents clear radio reception. The 'small ball' formation varies in size from two inches (5 cm) to a foot and a half (46 cm) in diameter and generally 'rolls around' the aircraft apparently unaffected by the movement of the aircraft. On one occasion a small ball (about six inches (15 cm) in diameter) of yellowish-white lightning formed on my left tiptank in an F-94B then rolled casually across the wing, up over the canopy, across the right wing to the tiptank and thence commenced a return, which I didn't note, but I was advised by my observer that it disappeared as spontaneously as it had arisen. I have seen this form several times but rarely for as long as a period which I would estimate to be about two minutes in duration. Sometimes the balls are blue, blue-green, or white though it appears to favor the blue-green and yellow-white. It might be of interest to you to know that subsequent to the 'small ball' rolling
over my aircraft, the aircraft was struck three times by conventional lightning bolts which melted four inches (10 cm) off the trailing edge of each tiptank and fused about a four inch section covering my tail lights."
In swamps and marshes, methane, CH4 (and also phosphine PH3), is released by decaying organic matter. When the methane ignites, either by spontaneous combustion or by electrical discharges produced during times of thunderstorm activity, luminous globes which float above the swamp can be seen. These are not plasma effects, but resemble them in appearance. They are called Ignis Fatuus (foolish fire), jack-o-lanterns,will-o-the~wisp, or simply swamp (or marsh) gas. The colors are reported to be yellow, sometimes red or blue. Thunderstorms and other electrical activity around swamps seem to stimulate this effect.
Occasionally observers have placed their hands into these luminescent gases without feeling any heat. Dry reeds did not catch fire. Copper rods did not heat up. Occasionally however paper was ignited.
There is little doubt that Ignis Fatuus is the source of some ghost stories and UFO reports.
In certain situations, cold dry air (from the Rocky Mountains) flows over warm moist air (from the Gulf of Mexico) which is moving in a different horizontal direction. As a result, wind shear and strong convection produce active thunderstorm cells along a line of instability some tens of kilometers ahead of the cold front. These thunderstorm cells and the opaque clouds connecting them are known as a squall line. Squall lines are the source of most tornadoes.
The characteristic feature of the tornado is the funnel-shaped cloud that hangs from the sky and moves around like the trunk of an
elephant. The destructive capability of the tornado is the result of an extremely sudden pressure drop of roughly 0.1 atmosphere between the inside and outside of the funnel. Winds can range in speed from 100 to 330 m/sec.
Without question, the most concentrated and powerful manifestations of atmospheric electricity occur in conjunction with tornadoes. Tornadoes are associated with continuous lightning, point discharges, and ball lightning. Early theories of the 19th century maintained that the tornado is a conducting channel for lightning between cloud and ground. Present thought attributes the origin of tornadoes to violent convective air motions near squall lines.
Although many convective events, such as isolated thunderstorms, dust devils, hurricanes, etc., occur in the atmosphere, these have energy concentrations much smaller than that of a tornado. Consequently, several researchers believe that a tornado can be maintained only by an intense and continuous lightning discharge along its axis. Such a discharge heats the air within the funnel, thereby causing violent updrafts and vortex motions. Whether or not this theory is correct, there is little doubt that the electrical power generated during a single tornado event is at least 2 x 1010 watts, or about 1/10 of the combined power output of all the electrical generators in the United States.
From radio emissions (spherics), it is estimated that about 20 lightning flashes occur each second in a tornado cloud. Assuming 20 coulombs per lightning discharge, the average current flowing through a tornado is about 400 amperes. Magnetic field measurements near a tornado indicate that such a current is not unreasonable. Using 109 joules per lightning flash, we find 2x1010 watts for the electrical power generated by a tornado.
Such estimates may be too conservative. Tornado lightning is reported to be brighter, bluer, and more intense than its thunderstorm counterpart. Long before a tornado is observed, lightning
interlaces the clouds. About 15 minutes prior to the appearance of the funnel, the lightning becomes intense and continuous. After the funnel descends, the sky is reported to be in a blaze of light with never ceasing sheet lightning.
Large hailstones are commonly produced both by tornadoes and by severe isolated thunderstorms. Hail is closely correlated with intense electrical activity. Observations of burned, wilted, and dehydrated vegetation, and odors of brimstone (burning sulfur) provide further evidence of electrical action. The tornado funnel is usually preceded by a peculiar whining sound, a noise indicative of coronal discharge.
Eyewitness accounts are interesting in the present context because it has been suggested that many UFOs are luminous tornado clouds whose funnels have not reached the ground:
If a researcher had never heard of a tornado, and were asked to compare the eyewitness accounts of tornadoes (such as these) with those concerning UFOs, he would probably find the tornado reports to be more fantastic and incredible. Luminous tornado clouds with no funnels to the ground are possible causes of several UFO reports.
During the heat of the day, the air temperature is high at the desert floor but decreases rapidly with height. At some critical temperature gradient (called the autoconvective lapse rate) violent upward convection of heated air occurs. Under certain desert conditions, the upward convection may be rather intense in small areas.
Rapidly rising air is replaced by cooler air which flows inward horizontally and asymmetrically, thereby creating a vertical vortex funnel. Such a desert vortex made visible by dust and sand particles, is known as a dust devil. Unlike the tornado, however, the dust devil begins from the ground and rises upward. Although it can sometimes blow a man over, it is much less powerful than a tornado.
Recent measurements indicate that strong electric fields are generated by dust devils. The precise nature of the charge separation process is not understood, but in this case at least, the electrical effects are almost certainly the result of convective motions and particle interactions.
Luminescent effects of dust devils have never been reported and would be extremely difficult to detect in the daytime. Since dust devils do not occur at night when the desert floor is cooler than the air above, this phenomenon can not explain UFOs reported at night.
Undersea volcanic eruptions began on the morning of 14 November 1963, only 23 km from the southern coast of Iceland, where the water depth was 130 m. Within 10 days an island was created which was nearly 1 km long and 100 m above sea level. Motion pictures showed clouds rising vertically at 12 m/sec to an altitude of 9 km. The cloud of 1 December contained intense, almost continuous light, presumably the result of large dust particles and perhaps electret effects of sulfur.
Aircraft flights through the volcanic cloud were made during periods of no lightning. Large electric fields were measured, sometimes exceeding 11,000 volt/m.
The production of lightning by volcanos is of considerable interest for atmospheric electricity. Nevertheless, there is no evident relation between volcano lightning and UFO reports.
Intense electrical activity has often been reported prior to, during, and after earthquakes. Unusual luminescent phenomena seen in the sky have been classified into categories:
The classification is somewhat ambiguous, but is rather descriptive of luminous events associated with earthquakes.
The earliest description of such phenomena was given by Tacitus, who describes the earthquake of the Achaian cities in 373 B.C.E. Japanese records describe luminous effects during many severe earthquakes. In the Kamakura Earthquake of 1257, bluish flames were seen to emerge from fissures opened in the ground.
Flying luminous objects are mentioned in connection with the earthquake at Yedo (Tokyo) during the winter of 1672. A fireball resembling a paper-lantern was seen flying through the sky toward the east. During the Tosa earthquake of 1698, a number of fireballs shaped like wheels were seen flying in different directions. In the case of the Great Genroku Earthquake of 31 December 1730 in Tokaido, luminous "bodies" and luminous "air" were reported during the nights preceding the day of severest shock. Afterwards a kind of luminosity resembling sheet lightning was observed for about 20 days, even when there were no clouds in the sky. One record of the Shinano Earthquake of 1847 states: "Under the dark sky, a fiery cloud appeared in the direction of Mt. Izuna. It was seen to make a whirling motion and then disappeared. Immediately afterward, a roaring sound was
heard, followed by severe earthquakes." In Kyoto in August, 1830, it is reported that during the night preceding the earthquake luminous phenomena were seen in the whole sky; at times, illumination emitted from the ground was comparable in brightness to daylight. In the Kwanto Earthquake of 1 September 1923, a staff member of the Central Meteorological Observatory saw a kind of stationary fireball in the sky of Tokyo.
The earthquake at Izu, 26 November 1930, was studied in detail for associated atmospheric luminescence. Many reports of sightings were obtained. The day prior to the quake, at 4 p.m., a number of fishermen observed a spherical luminous body to the west of Mt. Amagi, which moved northwest at considerable speed. Fireballs (ball lightning) and luminous clouds were repeatedly observed. A funnel-shaped light resembling a searchlight was also seen. Most witnesses reported pale blue or white illumination, but others reported reddish or orange colors.
That large electrical potentials can be created by the slippage or shearing of rocks is not surprising. Nevertheless, associated ball lightning and luminous clouds are of significance to this study. Of possible importance is the use of electrical measurements to provide some advance warning of an impending earthquake.
Mountains are sharp projections which rise from the conducting surface of the earth. The electrical potential of a mountain is essentially equal to that of the surrounding lowlands. Consequently, when an electric field is set up between cloud and ground, the potential gradient (or electric field strength) reaches a maximum between the mountaintop and the overlying clouds.
The large potential gradient which often exists on a mountaintop may give rise to a number of events related to coronal discharge.
Physiological effects of large electric fields are frequently reported by mountaineers. Many of these effects are also occasionally reported in connection with UFOs. In this section we summarize eyewitness reports from mountaintops.
1. A graduate student of the University of Colorado was climbing Chimborazo, a high and isolated mountain in Ecuador. The summit is a large flat plateau 400 meters in diameter and 6266 meters above sea level. He and a companion left their camp at 5700 meters on the morning of 1 March 1968. At 10 a.m. clouds started forming at the peak, and a small amount of graupel began to fall. When they reached the summit, between 2 and 2:30 p.m., there was considerable cloudiness. Just as they were about to take the traditional photograph of conquest, the graupel began to fall more heavily. Suddenly they felt an odd sensation about their heads, described as mild electric shocks and crackling and buzzing sounds. Their aluminum glacier goggles began to vibrate, and their hair stood on end. The climbers dived into the snow and waited. Thunder was heard in the distance. They found that whenever they raised their heads off the ground, the electrical effects recurred. It seemed as if there were an oppressive layer 50 cm above the surface. After waiting half an hour, the climbers crawled off the peak on their bellies. They proceeded in this manner for an hour and a half, 400 meters across the plateau and down the slope. After descending 60 meters, they found they could stand up. By this time the fall of graupel and the sounds of thunder had ceased.
During the 1870's and 1880's, the Harvard College Observatory maintained a meteorological station at the top of Pike's Peak. The journal of this expedition makes fascinating reading:
2. "16 July 1874. A very severe thunderstorm passed over the summit between 1 and 3 p.m., accompanied by mixed rain and hail. Sharp
flashes and reports came through the lightning arrester, to the terror of several lady visitors; outside the building the electric effects were still more startling. The strange crackling of the hail, mentioned before, was again heard, and at the same time the observer's whiskers became strongly electrified and repellent, and gave quite audible hissing sounds. In spite of the cap worn, the observer's scalp appeared to be pricked with hundreds of red hot needles, and a burning sensation was felt on face and hands. Silent lightning was seen in all directions in the evening, and ground-currents passed incessantly through the arrester."
3. "21 July 1874. Not only did the constant crackling of the fallen hail indicate the highly electrified state of the summit, but from the very rocks proceeded a peculiar chattering noise, as if they were shaken by subterranean convulsions."
4. "25 May 1876. At 6 p.m. continued thunder was heard overhead and southeast of the peak. The arrester was continually making the usual crackling noise. About this time, while outdoors, the observer heard a peculiar "singing" at two or three places on the wire very similar to that of crickets. When the observer approached near one of these places the sound would cease, but would recommence as soon as he withdrew two or three feet distant."
5. "18 August 1876. During the evening the most curiously beautiful phenomenon ever seen by the observer was witnessed, in company with the assistant and four visitors. Mention has been made in journal of 25 May and 13 July of a peculiar "singing" or rather "sizzing" noise on the wire, but on those occasions it occurred in the daytime. Tonight it was heard again, but the line for an eighth of a mile (200 in) was distinctly outlined in brilliant light, which was thrown out from the wire in beautiful scintillations. Near us we could observe these little jets of flame very plainly. They were invariably in the shape of a quadrant, and the rays concentrated at the surface of
the line in a small mass about The size of a currant, which had a bluish tinge. These little quadrants of light were constantly jumping from one point to another of the line, now pointing in one direction, and again in another. There was no heat to the light, and when the wire was touched, only the slightest tingling sensation was felt. Not only was the wire outlined in this manner, but every exposed metallic point and surface was similarly tipped or covered. The anemometer cups appeared as four balls of fire revolving slowly round a common center; the wind vane was outlined with the same phosphorescent light, and one of the visitors was very much alarmed by sparks which were plainly visible in his hair, though none appeared in the others'. At the time of the phenomenon snow was falling, and it has been previously noticed that the "singing" noise is never heard except when the atmosphere is very damp, and rain, hail, or snow is falling."
6. "16 June 1879. (During afternoon). One of those electric storms peculiar and common to Pike's Peak prevailed. A queer hissing sound issued from the telegraph line, the wind-vane post, and another post standing in a deep snow drift near by. Observer stepped out to view the phenomenon, but was not standing in the snow drift long, when the same buzz started from the top of his head; his hair became restless, and feeling a strange creeping sensation all over his body, he made quick steps for the station."
7. "10 July 1879. At 5 p.m. the hail turned to snow, and ceased at 5:30 p.m., the wind being gentle throughout. On stepping to the door at 6 p.m., observer states that he felt a peculiar sensation about the whole body, similar to that of an awakening limb after being benumbed; that his hair stood straight out from his head, and seemed to produce a peculiar "singing" noise like that of burning evergreens; the telegraph line and all metallic instruments producing a noise like
that of swarming bees. When he put on his hat, the prickly sensation became so intense that he was compelled to remove it, his forehead smarting as though is had been burned for fully three hours later. At 7 p.m. the electric storm had ceased."
With the exception of tornado situations described earlier (where heat is also present), it is not likely that electrical sensations are anywhere more intense than on mountaintops. UFO reports sometimes indicate creepy, crawling sensations, much less pronounced, however, than those experienced by mountaineers.
A meteor is a streak of light produced by the interaction with the atmosphere of a solid particle (or meteoroid) from interplanetary space. Most meteoroids, particularly those that appear on schedule during certain times of the year, are probably dust balls which follow the orbit of a comet. When they enter the atmosphere they produce short-lived streaks of light commonly known as shooting stars.
A fireball or bolide (Greek for javelin) is a meteor with a luminosity that equals or exceeds that of the brightest planets (apparent magnitude -5). A solid object called a meteorite may be deposited on the earth's surface after a bolide, but never after scheduled meteor showers. The appearance of a bolide is random, and not correlated either in space or in time with comet orbits and the usual meteor showers. Bolides are believed to be caused by solid fragments from the asteroid belt, whereas the scheduled meteors are caused by dust balls from cometary orbits.
When a meteoroid passes through the upper atmosphere, a shock wave is generated, accompanied by intense heating of the surrounding air and the meteoroid surfaces. Atoms which boil off the meteoroid surface possess thermal speeds of about 1 km/sec and directed velocities of up to 72 km/sec. They collide with surrounding air molecules, and create an envelope of ionization and excitation. A meteorite only a few tens
of centimeters wide may be surrounded by an ionized sheath of gas some tens of meters or more in diameter. De-excitation and recombination processes give rise to the long visible trail behind the meteoroid. Meteor trails are visible at altitudes between 110 and 70 km.
The brightest bolides can cast shadows over a radius of 650 km. To be as bright as the full moon, meteoroids of at least 100 kg are required. About 1500 meteoroids enter the earth's atmosphere each year, each with a mass greater than 100 kg.
The visual appearance of a bolide differs considerably from that of a shooting star. Vivid colors and color changes are common. Bolides have been seen to break apart, with fragments circling slowly on the way down or flying in a line or in an apparent formation. The trajectory of a bolide can appear almost horizontal to the observer. Because of the extreme brightness and the large diameter of the ionization envelope, distances to bolides are always underestimated, particularly if it should flare up toward the end of the descent. Odors of brimstone near the impact point have also been reported.
Meteor trains associated with bolides sometimes remain luminescent for an hour or so. Such a train may appear as a glowing column about one kilometer in diameter. The mechanism which allows certain meteor trains to glow for so long a time is not known. Radar trails of ordinary meteors last only 0.5 sec. Spectral analysis of glowing meteor trails reveals many bright emission lines from excited air atoms. Radiation from the hot surface of a meteoroid has also been detected on rare occasions. These emission lines reveal only common elements (such as iron, sodium, magnesium, and other minerals), implying a chemical composition similar to the earth and to the asteroids. During the day, a bolide train is seen as a pillar of dust at lower altitudes rather than as a glowing column in the upper atmosphere.
Some minutes after exceptionally bright bolides, some witnesses have heard sounds described as thunder,
the boom of a cannon, rifle or pistol fire, etc. These sounds are produced by the fall and deceleration of a massive meteorite or of several fragments.
There are also a significant number of reports concerning sounds heard while the bolide was still descending from the sky, perhaps a hundred kilometers above the ground. These sounds are described as hissing, swishing, whizzing, whirring, buzzing, and crackling, and are attributed to bolides with an average apparent magnitude of -13 (about the brightness of the full moon). Such noises could not have propagated all the way from the meteorite, since sound travels too slowly.
At one time it was believed that people who observed bolides imagined the sounds, as a psychological association with noise from sparklers and other fireworks. Meteor sounds are now regarded as physical effects. On several occasions the observer first heard the noise and then looked upward to seek the cause. (Similar noise has also been reported during times of auroral activity.)
One hypothesis is that low frequency electromagnetic radiation is emitted by bright bolides and detected by human sense organs. Human subjects exposed to radar beams of low intensity have perceived sensations of sound described as buzzing, clicking, hissing, or knocking, depending on the transmitter characteristics. A pulse-modulated signal with a peak electromagnetic radiation flux of 4 watt/m2 at the observer was perceived as sound by subjects whose audible hearing was good above 5 kHz. If the background noise exceeded 90 decibels, the radio frequency sound was masked, but earplugs improved the reception.
During the fall of one of the largest bolides, near Sikhote-Alin, near Vladiovostok (USSR), an electrician on a telephone pole received a strong electric shock from disconnected wires at the instant the bolide became visible. The shock may have been due to other causes, but the possibility of strong electromagnetic effects is not ruled out.
At present, measurements made during smaller meteor events (of the dust ball variety) give no indication of significant radio emission. Magnetic effects are insignificant.
Another conjecture is that atomic collisions in the vicinity of a meteorite bring about a separation of charge along the ionization trail of the bolide. For coronal discharge effects to occur at ground level, however, the bolide would have to separate many thousands (or even tens of thousands) of coulombs about 30 km. along its ionization trail. Such a process seems unlikely.
The noises which appear simultaneously with the bolide are not understood. If strong electrical fields accompany a bolide, other effects such as lightning or ball lightning may occur. Both lightning and ball lightning have occasionally been reported in clear non-stormy weather. There are also several reports of large chunks of ice falling out of cloudless skies. They are not believed to have fallen from aircraft. The ice chunks may arise from electrical effects of bolides, or (more probably) may be the meteorites themselves.
The existence of anti-protons, anti-electrons, anti-neutrons, etc. is no longer a subject for speculation. A particle and its anti-particle annihilate one another on contact, creating radiant energy. Consequently, we do not find antimatter on the earth. It is not known how much antimatter exists elsewhere in the universe.
In June of 1908, a bolide of enormous magnitude fell near the Tunguska River about 800 km. north of Lake Baikal in Siberia. The light was possibly as bright as the sun and was seen over a radius of 700 to 1000 km. Acoustic noises from the shock were heard as far away as 1000 km. No trace of a crater has ever been found, but within a radius of 40 km., exposed trees were flattened with their tops pointing radially away from the epicenter. Witnesses felt intense heat on their skin. Metal objects near the impact point were melted. Trees were scorched for 18 km around. An earthquake was detected on seismographs at the Irkutsk Magnetic and. Meteorological Observatory which corresponds
in time to the impact of the bolide. Barometric waves circled the globe. Magnetic disturbances were reported on many continents. The energy released by the Tunguska bolide is estimated between 1016 and 1017 joules (the energy range of hydrogen bombs).
Several million tons of dust may have been injected into the atmosphere. For several weeks after the event, luminous clouds in Europe and Western Siberia made it possible in certain areas to read at midnight under the open sky. The observatory at Irkutsk could not see the stars. A traveler noted in his diary that night never came. The nature of these luminous clouds is still a matter of debate.
The composition of the bolide and the cause of the explosion are not known. A very massive meteorite should impact with the ground and leave a large crater (even though the meteorite and part of the ground would be immediately vaporized). The Tunguska bolide, however, apparently exploded some 3 km or so above ground level.
Several hypotheses have been advanced concerning the nature of the bolide and the explosion:
The first two hypotheses are conventional. Even so, it is extremely difficult to evaluate quantitatively the optical, acoustical, and thermal effects that might occur under all possible circumstances. The remaining hypotheses were proposed to explain the thermal effects.
The fourth hypothesis seems unlikely. A fission reaction of such magnitude would require that large almost-critical masses of fissionable material be suddenly brought together. A fusion reaction would require an initial temperature of several million degrees Kelvin. Neither of these possibilities seems reasonable.
The fifth hypothesis has measurable consequences. When matter and antimatter come into contact, they annihilate each other, and produce gamma ray, kaons, and pions. If an antimatter meteoroid were to collide with the atmosphere, negative pions would be produced. The nuclei of the surrounding air atoms would absorb the negative pions and release the neutrons.
Nitrogen nuclei would capture the neutrons and be turned into radioactive carbon-14. As carbon dioxide, the radiocarbon would be dispersed throughout the atmosphere and be absorbed by living organisms.
The energy of the Tunguska bolide was estimated from a study of the destruction that occurred. The initial quantity of antimatter and the amount of radioactive carbon dioxide produced was then estimated. Sections of trees which grew in 1908 were analyzed for radiocarbon. The conclusion of several scientists is that the Tunguska meteor was probably not composed of antimatter. The best guess is that a comet collided with the earth in June, 1908.
Nevertheless, the hypothesis of antimatter meteorites is intriguing. If a significant amount of antimatter does exist in the universe, it is possible that antimatter supernovae might eject tiny grains of anti-mass at relativistic speeds. Such a grain might penetrate our galaxy and collide with the earth's atmosphere. Entering at relativistic speeds, the grain might survive until it reached the troposphere. A fraction of a microgram of antimatter would destroy an equal mass of matter and release many megajoules of energy, perhaps creating luminous spheres. However, the annihilation of a fast antimatter meteorite has never been calculated in detail, and possible visual effects are unknown. Moreover, since small grains of antimatter would leave virtually no trace, this hypothesis remains as pure speculation.
Two articles and one popular book have been written on plasma interpretations of UFOs by P. J. Klass. Klass was impressed by reports of UFOs in close association with high tension power lines near Exeter, New Hampshire. Many popular books assert that UFOs are extraterrestrial spaceships which hover over power lines to refuel. Klass believes that some UFOs are an unusual form of coronal discharge analogous to St. Elmo's fire.
In his first article, ball lightning is assumed to be a manifestation of extreme coronal discharge. Klass points out that ball lightning and the Exeter UFOs compare favorably with regard to color, shape, sound, dynamics, lifetime, and size. According to those reports, the diameters of the UFOs ranged from the size of a basketball to 60 meters. This size range may be due to the difficulty of making distance estimates at night without visible reference points.. Exeter is close enough to the sea for salt to form on high tension wires and had very little rainfall that summer to wash away the salt, thus providing points from which coronal discharge could occur.
Criticisms are
Klass also examined other UFO reports including those seen at aircraft altitudes. In his second article, which is concerned with the general UFO problem he asserts that ball lightning may occur under many situations, and consequently may be the cause of many unusual UFO sightings. Various aspects of ball lightning and the laboratory creation of luminous plasma by microwaves and gas discharges are briefly discussed. Klass argues that plasma blobs would have the same characteristics and would cause the same effects as those occasionally attributed to UFOs, including the abrupt (sometimes explosive) disappearances, maneuvers near aircraft, rapid accelerations, stalled automobiles, heat, prickling sensations, irritated eyes, etc. He discusses one observation of an UFO seen through Polaroid sunglasses and one report of an agitated magnetic compass.
The book, UFOs Identified, is an expanded version of the two articles, and contains background of the author's investigation. He discusses ball lightning, the behavior and appearance of UFOs, radar and photographic evidence, the various reactions to his articles, and
an account of a couple who claim they were held prisoner in an UFO. The book does not attempt to summarize any of the fundamental principles of atmospheric electricity, plasma physics, or atmospheric dynamics.
About reports of automobiles stalled near UFOs, Klass writes:
"Because a plasma contains a cloud of electrified particles, there is no doubt that if an auto battery were enveloped by such a plasma the battery could be short-circuited. But it is difficult to explain how an UFO-plasma could gain entry to the car battery in the engine compartment without first dissipating its energy to the metal body of the car. Another possible explanation is based on the fact that an electric charge in the vicinity of a conducting surface, such as a car's hood, creates a mirror image of itself on the opposite side of the conducting surface." The implication here is mistaken: the image charge discussed in electrical theory is not an actual charge on the other side of a metal shield, but a mathematical fiction that is used to describe the alteration of the electric field by redistribution of electric charges on the metal shield.
Alleged automobile malfunctions are discussed in Section III, Chapter 5 of this report, and was purposely omitted here. However, a few remarks may be in order. As Klass points out, some motorists have reported that both headlights and engine failed. Others have reported that only the engine or only the headlights failed. Often police cars have chased UFOs for tens of kilometers so engine failure does not always occur. Moreover, no unusual magnetic patterns have so far been detected in auto bodies.
When radar was secretly being developed by the RAF prior to the London Blitz (World War II), some of the local people of Burnhamon-Crouch were convinced that the mysterious masts recently erected had stopped passing automobiles. Presumably when the purpose of radar became known, cars were no longer stalled.
In addition to ball lightning and coronal discharge, he also suggests tornado clouds with no funnel to ground, luminescence generated
during snowstorms, rotating dust vortices, and small charged ice crystals. Another one of his ideas is that occasionally a highly charged aircraft may release ions into a large wingtip vortex. The vortex remains luminous for awhile, to be encountered shortly thereafter by another aircraft. Although coronal effects occur on aircraft surfaces, it is unlikely that a lightning ball could detach from an aircraft and remain luminous for more than a few seconds.
On 27 and 28 October 1967, several physicists expert in either plasma physics or atmospheric electricity met in Boulder, Cob, to discuss the UFO problem with staff members of this project. Participants in the plasma UFO conference were:
Marx Brook: New Mexico Inst. of Mining and Technology
Keith A. Brueckner: University of California (San Diego)
Nicholas C. Christofilos: University of California (Livermore)
Ronald T. H. Collis: Stanford Research Institute
Edmond M. Dewan: Air Force Cambridge Research Lab.
Herman W. Hoerlin: Los Alamos Scientific Lab.
Bernd T. Matthias: University of California (San Diego)
Arnold T. Nordsieck: Santa Barbara, California
Marshall N. Rosenbluth: James Forrestal Research Center
John H. Taylor: University of California (San Diego)
UFO Study Members
Various aspects of atmospheric electricity were reviewed, such as ball lightning, and tornado and earthquake luminescence. Unusual UFO reports were presented for discussion. These included a taped report by a B-47 pilot whose plane was paced for a considerable time by a glowing object. Ground radar reported a pacing blip which appeared to be 16 km from the aircraft. After review the unanimous conclusion was that the object was not a plasma or an electrical luminosity produced by the atmosphere.
Participants with a background in theoretical or experimental plasma physics felt that containment of plasma by magnetic fields is not likely under atmospheric conditions for more than a second or so. One participant listed the characteristics that would be expected to accompany a large plasma. These are
Another plasma physicist noted that a plasma explanation of certain UFO reports would require an energy density large enough to cause an explosive decay. Atmospheric physicists, however, remarked that several reports of ball lightning do indicate unusually high energy densities.
All participants agreed that the UFO cases presented contained insufficient data for a definitive scientific conclusion.
The strange case in St. Petersburg, Florida is discussed in: