Oct 12, 1999

French Nobel Laureate turns back clock

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French Nobel Laureate turns back clock:


Marshall's global experiment, von Braun memories
evoked during August 11 solar eclipse


Oct. 12, 1999: At any given spot along its path, the Aug. 11, 1999, total eclipse offered up to 2-1/2 spectacular minutes of total lunar coverage of the sun. But for two NASA researchers, the show's not over. They're just getting started probing a 50-year-old mystery.

Before the eclipse, Dr. David Noever and Ron Koczor of NASA's Marshall Space Flight Center decided to check some hard-to-believe measurements reported 50 years ago by Nobel laureate Maurice Allais.

In 1954, Maurice Allais reported that a Foucault pendulum exhibited peculiar movements at the time of a solar eclipse. If true, his finding raises new questions about the nature of such phenomena.

The inventor of the gyroscope, Jean Bernard Leon Foucault, demonstrated during the 1851 World's Fair that a pendulum could track the rotation of the Earth. Remarkably, little more than two long-term scientific records for Foucault pendulums have been published. Both experiments were conducted by eventual Nobel Prize winners: Heike Kamerlingh-Onnes, who won the 1913 Nobel prize in Physics for his investigations on the properties of matter at low temperatures (which led to the production of liquid helium), and Allais, who won the 1988 Nobel prize in Economics for his contributions to the theory of markets and efficient use of resources.


Reporting sites included three stations in Austria (Austrian National Meteorological Institute, Central Institute for Meteorology and Geodynamics; University of Vienna, Experimental Physics Department); three stations in Italy (Department of Physics, University of Trento, University of Trieste, Marigliano, Italy); one station in both France (Scintrex/Ids Europe, St Jean de Braye) and Germany (Department of Physics, Ernst-Moritz-Arndt-University Greifswald University-Observatory, Germany); 7 stations in the Persian Gulf (coordinated by Edcon, Inc., Denver, CO); 1 station in Turkey (Metrology Institute, Kocaeli, Turkey); and 7 stations in the United States (NASA/MSFC, Huntsville; Dept. of Geological Sciences, Virginia Tech; Department of Physics, University Louisville; Ball Aerospace & Technologies Corp, Boulder, CO; Edcon, Inc., Denver, CO; Micro-g Solutions, Inc., Boulder, CO; LaCoste & Romberg LLC, Austin, TX).


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In a marathon experiment in 1954, Allais released a Foucault pendulum every 14 minutes - for 30 days and nights - without missing a data point. He recorded the direction of precession (in degrees) at his Paris laboratory. This energetic show of human endurance happened to overlap with the 1954 solar eclipse. It also covered slightly more than one orbit of the Earth by the Moon. During the eclipse, the pendulum took an unexpected turn, changing its angle of rotation by 13.5 degrees.

Left: Prof. Maurice Allais.


Both before and after the eclipse, the pendulum experienced normal rotation, the Foucault effect, of 0.19 degrees/minute. This 13.5-degree excursion in the angular plane persisted throughout the length of the eclipse, a total of 2.5 hours of observations from eclipse start on Earth's west limb to end on the east limb. In 1954, it was 2 hours, 34 minutes. In 1959, it was 2 hours 14 minutes. Both were partial eclipses at the local point of observations. The total observation time was continuous for 30 days; it just happened to coincide with the 2.5 hours of the eclipse. He was not looking for any effect here. Allais got similar results when he later repeated the experiment during a solar eclipse in 1959.

For the eclipse of 1999, NASA/Marshall joined several teams of scientists investigating the effect.

"The initial interpretation of the record points to three possibilities," says Noever of NASA/Marshall, "A systematic error, a local effect, or the unexplored. To eliminate the first two possibilities, we and several other observers will use different kinds of measuring instruments in a distributed global network of observing stations."


The Earth's rotation as seen with the help of a solar eclipse


Left: The eclipse and the pendulum - How the pendulum's swing angle changed during the 1954 eclipse. In an American J. of Physics (58, 530, 1990; G.T. Gillies) review, the summary of Allais' work reads: "A physicist (who later won a Nobel prize in economics) finds a gravitational anisotropy at the level of 5 micro-G. (5x10-6 ).

The plane of the oscillation of the pendulum shifted approximately 15 centesimal degrees during the eclipse (approximately 13.5 degrees). An azimuthal curve traced for the period extending from June 28, 1954 (8 p.m.) to July 1, 1954 (4 p.m.).

The Earth's rotation as a clock as seen from Earth

The pendulum keeps its initial line of swing, while the Earth rotates underneath it and sweeps out a clock face rotation that depends on the observer's distance from the equator.

The Earth's rotation as a clock as seen from the Moon

From the 1989 mission review that Eric Jones, Lunar Surface Journal, did with Apollo 15 lunar module LM pilot, Jim Irwin.

Question: When you got back in the LM, were you conscious at all that the Earth had rotated during the EVA? I was wondering if anybody was conscious of the rotation of it and using it as a clock.

Irwin - "I never looked at it. I just wish I'd taken more time to look at the Earth. (Chuckling) I would have liked to have just stretched out on the surface and watched the Earth for a while, but I never had that opportunity."


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Data collection began on August 11. The times of the solar eclipse were 3-9 a.m. in North America, and 9 a.m.-3 p.m. in Europe and Middle Asia. These times can be adjusted for exact locations, for instance, in Boulder, Colorado, a data set for recording would be about 2:30 a.m., continuing until 8:30 a.m. That would cover the approach of the shadow, the actual eclipse, and the retreat of the shadow.

Data are being proof-checked on all the major local and global variables: atmospheric pressure, magnetic and gravity fields, seismic and thermal effects. One goal of this wide network of investigators and their diverse instruments was to compare and contrast the Aug. 11 events with the results of several earlier eclipses, from 1954 to 1995. This distributed network included records using six major instrument types: barometers, magnetometers, seismographs, and gravity meters, along with large video files tracking both stationary and rotating (Foucault) pendulums around the world.

Two effects of an eclipse that don't require any complex instruments to register are its optical shadow and the cooler temperatures that lag by about half an hour the eclipse maximum (called second contact). Very small pressure waves due to this cool air can even be measured by some microbarometers (0.002% atmospheric pressure change). Often giving an eerie quiet, this 2-5 degrees cooler air can give rise to sporadic wind speed changes that usually decrease locally.


From Allais' 1988 Nobel autobiographical lecture: "During the total eclipses of the sun on June 30, 1954, and October 22, 1959, quite analogous deviations of the plane of oscillation of the paraconical pendulum were observed..." Allais' observations from 1954 and confirmed in 1959 registered as over 12.5 times the background noise described by the motion of a Foucault pendulum.

But during the eclipse one set of Marshall experiments tracked changes that required highly sensitive instruments. For example, to scout out any possible effects of an eclipse, even the most ordinary of pendulums (if properly constructed and controlled) can measure small variations as low as 3 millionths of background levels for some interesting eclipse-related variables.

On Aug. 11, the major site in the path of totality was Austrian, at the Kremsm端nster Observatory. As an historic scientific site, Kremsm端nster is a short distance from Linz, Austria, where the pioneering astronomer and celestial calendar maker, Johannes Kepler, worked at various times with Tycho Brahe. Today, the observatory displays the sextant used by Kepler from the 1590s. This site maintains meteorological records since 1763.


The same scientific dilemma can come in many guises

Here's a list of scientific articles that address measurements of apparent gravitational anomalies. Some are related to solar eclipses, some are not.

[The speed of gravity - what the experiments say. T. van Flandern, Physics Letters A. vol.250, no.1-3, Page: 1-11 (1998)] (alternate PDF document)

Total eclipses of the Sun by the Moon reach maximum eclipse about 40 seconds before the Sun and Moon's gravitational forces align. If gravity is a propagating force, this 3-body (Sun-Moon-Earth) test implies that gravity propagates at least 20 times faster than light.

The Earth accelerates toward a point 20 arc seconds in front of the visible Sun, where the Sun will appear to be in 8.3 minutes. Thus, the acceleration now is toward the true, instantaneous direction of the Sun now, and is not parallel to the direction of the arriving solar photons now.

[Ghosh, A. in "Progress in New Cosmologies: Beyond the Big Bang", H.C. Arp et al. (Ed.) Plenum Press (1993)] - The spectrum of light coming from the edge of the sun shows a redshift different from the center.

[Sadeh, D., Knowles, S.H., and Yaplee, B.S., Science, 159, 307, (1968)] - Sadeh, et al. reported that the 21 cm signal coming from the star Taurus A suffered a redshift of 150 Hz while grazing the sun at a distance of 5 solar radii on 15 June 1967.

[Merat, P., Pecker, J-C. and Vigier, J-P. Astronomy and Astrophysics, 174, 168, (1974).] - Merat et al. reported that the 2292 MHz signal from Pioneer-6 was also found to be subjected to a redshift when it passed behind the sun.

[Zhou, S. W.; Huang, B. J., "Abnormalities of the time comparisons of atomic clocks during the solar eclipses", Nuovo Cimento C, vol. 15 C, no. 2, Mar.-Apr. 1992, p. 133-137.] Time comparisons of two atomic clocks were made during the solar eclipses of September 23, 1987, March 18, 1988, and July 22, 1990. Abnormal variations of the time comparisons during the solar eclipses are confirmed, not only on a comparison clock pair, but also on many comparison clock pairs by means of three different methods during three solar eclipses.

Perhaps the most revealing instances, other than the nearly 2-1/2 hours of observations centered on the partial eclipses, would be the four significant contacts in any eclipse: first (point of initial optical alignment), second (totality), third (point of initial optical departure), and fourth (end). Freeze frames of the pendulums on these instances are the first steps to understanding the data. All these times and locations are synchronized and compared. Each video when digitized is nearly half a terabyte (trillion) of data unless compressed. In additional to control data before and after the eclipse, a number of sites have provided comparison inputs from their archives during normal operation and during lunar opposition 2 weeks after the eclipse.

A general scientific proof-test is to find out if, for any variables, did an eclipse signal exceed the background noise levels during normal operation by a factor of 3 or more. The second question to answer is whether there is a match to any significant timing for a related eclipse event. The third question to ask is whether competing artifacts, such as pressure changes or seismic effects, come into play for those times.

Finally when these local questions are answered, a global solution is needed. How many of the readings synchronize with each other, both positive and negative?

On Aug. 12, the day after the last eclipse this millennium, the Paris daily newspaper, Le Figaro, indicated the clock is still ticking in its title, NASA studies the observations of Maurice Allais: "It will take [time] to obtain the analyses. At 87 years, Maurice Allais waits patiently while going each day to his swimming pool. "

The Greifswald, Germany site ran their control experiment from approximately equal initial directions (NW/SE swing plane); then let the video run for 6 hours. There are 3 restarts at least in each video based on the last angle and approximately a 2 hour decay time for the pendulum release. The first control was done on Aug. 4 and the eclipse data was taken on Aug. 11. The beginning and final positions are superimposed in a short two frames of animation which loops. The last image shows that over 6 hours, the eclipse position is ahead of the control data. The quantitative parts are complicated by the video angle, but it does seem that a huge volume of video data is potentially representable with this approach: superimpose the control and eclipse data from initial and start positions all in the same image.


Demonstration of Foucault effect; Kremsm端nster Observatory, Austria, August 11, 1999. Rotation is shown at the maximum in pendulum (shown as round shadow with smaller laser target; back and forth swing motion not shown). The marks shown radiating beneath the pendulum itself are hourly tick marks for ideal pendulum behavior. This particular set of images shows the approximately doubling of the forward rotation (30 minutes per tick mark). Universal time is shown at lower right. The thirty-minute image separation demonstrates that the floor is moving underneath the pendulum which always keeps its initial swing direction while the earth rotates. At this latitude, the rotation from right to left in the image is approximately 11.2 degrees per hour.


This animation shows one stroke of the linear swing motion and 4 hours of rotation of the floor relative to the pendulum is shown by the circular (peripheral motion) path of the pendulum weight. These are taken as freeze frames at the end of each back and forth swing and spaced at 30 minute intervals (or around 4.6 degrees of rotation seen from above). This is an image from almost 72 feet above the pendulum; or 6 stories up. In other words, this is not as it would appear to an observer since there are the two separate modes being superimposed in the same animation. It however does illustrate a lot of the issues involved in the pendulum discussions. Since this is outside the path of totality, it shows normal behavior, e.g. the rotation is as expected at around 9.3 degrees per hour. Credit: University of Louisville, Department of Physics.

When Allais won the Nobel in 1988 at age 77 he had all but given up hope of acknowledgement, but as a commentary on his prize remarked at the time: "It was not till now that we discovered his greatness. Allais has been studied by us for many years and we are now certain he is a giant."

Allais has published some 1,500 scholarly papers, including studies in gravity, geophysics, history and economics. Rocket pioneer, Wernher von Braun, NASA/Marshall's first director, first became interested in Allais' experiments in 1958, when early investigations began to look at predicting satellite trajectories in orbital mechanics.

With current Marshall video records in digital form and some powerful graphical and tracking routines in software, the task is still very challenging if results could be just spread out flat on a table in raw form.

Allais' work shares some features with the latest explanations offered to explain the anomalies in the Pioneer spacecraft - now more than 6 billion miles from the Sun. As a low-friction projectile subject to inertia and gravity as it moves through space, a pendulum is sometimes compared in its motion to an artificial satellite - and thus a unique laboratory probe of the properties of space itself.

As the Paris daily, Le Figaro, continued: "Why is NASA interested? Scientists have detected an incomprehensible acceleration of three probes leaving the solar system, Pioneer 10 (1972), Pioneer 11 (1973) and Ulysses (1989). In the files of the agency, the father of American rocketry, the German Wernher von Braun, had supported Maurice Allais in 1958."

In the most recent September 19 correspondence from Professor Allais, he indicated: "In these types of experiments one needs to proceed slowly. On the whole, the repetition of these experiments offers NASA an exceptional interest."

Web Links Decrypting the Eclipse--August 6, 1999
Peering Through a Hole in the Sky--June 19, 1999
Infralow solar gravity
The Millennium's Last Solar Eclipse -- from Sky &Telescope
Fred Espenak's Solar Eclipse Home Page -- at the NASA/Goddard Space Flight Center
Autobiography of Maurice Allais -- Copyright ©1999 The Nobel Foundation
The Foucault Pendulum -- a excellent tutorial discussion by by Professor B. Nickel, Physics Department, University of Guelph. This web site also reviews some peculiarities in pendulum motion detected by experiments at the University of Guelph.
Three Spacecraft Reveal Unexplained Motions -- from Newswise
The Apparent Anomalous, Weak, Long-Range Acceleration of Pioneer 10 and 11
Unexplained sunward deceleration
Big Bang Acceleration -- Observations of supernova explosions halfway back to the Big Bang give plausible evidence that the expansion of the universe has been accelerating since that epoch, approximately 8 billion years ago and suggest that energy associated with the vacuum itself may be responsible for the acceleration. R.P. Kirshner, Harvard-Smithsonian Center for Astrophysics, Proc. Natl. Acad. Sci. 96, 4224-4227 (1999).
Harvard/NASA Abstract
Eclipse pendulum
Null result, 1990
Earth-moon-pendulum system
Solar rotation and pendulum
Gravity wave detector
A possible explanation for the anomalous acceleration of Pioneer 10
Indications of anomalous accelerations I
Anomalous Pioneer accelerations --abstract
Anomalous Pioneer accelerations II--full pdf file
Prosaic explanations: Asymmetric radiation
Prosaic explanations: spacecraft waste heat


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