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Benvenuti in queste pagine dedicate a scienza, storia ed arte. Amelia Carolina Sparavigna, Torino

Friday, September 30, 2011

Fairy chimneys in Peru

Fairy chimneys in Peru , Amelia Carolina Sparavigna, Dipartimento di Fisica, Politecnico di Torino, Torino, Italy

The erosion of water and wind on the rocks is able to create beautiful landscapes. Some places are well-known and have been declared natural heritage sites by UNESCO; some others are in desert and hostile regions, hard to visit. In most cases, just the local population knows these landscapes. In this post we will see that the simple action of some users of World Wide Web services, such as the Google Maps, in uploading their pictures, allows the discovery, study and perhaps future preservation of some of them. We will see in particular the case of some fairy chimneys in Peru, in the district of Pampachiri, Apurímac.
Before talking about this Peruvian landscape, let us discuss briefly the nature of these rocky structures, tall and thin cusps of rock protruding from the land. They are named in several manners [1]. These pinnacles are considered as "tent rocks", "fairy chimneys" or simply "earth pyramids", according to their shapes. Another name is “hoodoo": at first sight, this name seems to be derived from "hood" because of the structure looking like a sort of "dwarf hat", but probably its etymology is different [2]. Hoodoo is the common term used to describe the rock chimneys found in the western United States and Canada.
The fairy chimneys consist of a relatively soft rock. Some of them have on the top a harder stone, less easy to erode: the result is a geological structure resembling that of a chimney. These structures typically arise within sedimentary rocks or volcanic formations. The height of these chimneys can be of tenths of meters. Their shapes are affected by the existence of different and alternate layers of materials having different strength. In some regions, there are the freezing of water and the gravity that are creating these structures. The process is known as "frost wedging". The water, that percolates in the cracks of rocks, freezes and then expands, acting as a wedge and breaking the rocks apart [1,3]. This is the same action chiseling the landscape of Dolomites, the mountain range located in northeastern Italy [4]. During the night, when the temperature goes below the freezing point, the water into the fractures of rock turns into ice. The corresponding expansion of volume increases the distance between the sides of fractures. During the day, the sun warms the rocks and water melts. So separated from the bulk, some parts of the rock fall for gravity. In the case that the fairy chimneys are made by tuff rocks from volcanic eruptions, the erosion is due to wind and rain. In Italy, there are several areas with gullies (calanchi) and pinnacles, chiseled by water and wind. Well-known are the Calanchi di Volterra in Tuscany, but several others interesting places are in Abruzzo [5].
Among the best-known landscapes having fairy chimneys, there is that of Cappadocia, Turkey [6]. Besides the importance of this geophysical area, the region is quite interesting because Cappadocians carved their homes into the soft rock (see Fig.1). During the medieval era, this area becomes a refuge for Byzantine Christians. The people established monastic settlements and churches inside the pinnacles. According to [6], the Göreme Open-Air Museum in Cappadocia has the best-preserved collection of chapels and houses, most dating about the 11th Century [7]. The life in Cappadocia was even more complex, because, due to the persecution, the local Christians often had to hide themselves. It seems that, alarmed by the hoof beats [6], they could abandon the caves in the pinnacles to find a refuge in the underground. Beneath the ground of Cappadocia, archaeologists found a network of subterranean villages, the largest discovered is almost 10 levels deep, with narrow passages among them [6-9].

Fig.1. Fairy chimneys in Cappadocia (picture by Zeynel Cebeci, of a site at Ürgüp - Nevşehir, Turkey).

Not only Cappadocia has some houses inside the natural chimneys. We can find them also in Peru, near Pampachiri and San Pedro de Larcay. This is a region having several interesting places for geophysical and archaeological researches. In fact, there is the archaeological site of Wallpa Wiri, having structures of Incas age [10,11]. Moreover, this region possesses a large structured system of carved stones, used as landmarks for agricultural purposes, system created in the Late Horizon period of Peruvian prehistory [11]. Analyzing this landscape within its agricultural and social context [11], the researcher provided evidence of water distribution and management of the irrigation cycles by the Incas; that is, there was an administration and management of the local agricultural processes by the central government. A survey of the region with Google Maps reveals the presence, at south-west of San Pedro, coordinates -14.178624,-73.592713, of several "qochas", ponds with a diameters of about 100 meters (see Fig.2).

Fig.2. Qochas near San Pedro. The average size is about 100 meters.

Linked together by a network of canals, qochas form a system of water and soil management [12]. This system is probably of pre-Incaic origin.
Unfortunately, the satellite map corresponding to this area has a limited resolution. However, Google Maps has an interesting feature: it is possible to drag the icon of the street view on the map and see if there are photos of the landscape uploaded by users. Doing this dragging, the location of the pictures appears as blue dots on the map (see Fig.3). In this manner, anybody using the map can have some information on the landscape corresponding to the specific location. There are no photos of the qochas of San Pedro, but many pictures of nearby locations, uploaded by Max Altamirano Molero [13]. Besides being very beautiful, the pictures display the existence of a forest of fairy chimneys. The location in the Pampachiri district is given in the map of Fig.3.

Fig.3. The position of San Pedro de Larcay, Peru, in the district of Pampachiri is given by the green arrow. The location of the fairy chimneys is given by the blue dots corresponding to the photo

Fig.4. The image shows a part of the very interesting set of images by Max Altamirano Molero. To see them, the reader can visit [13].


To the author’s knowledge, the pictures by Altamirano are among the best existing documentations of fairy chimneys in Peru . In fact, among the pictures that Altamirano has collected on a site (see Fig.4 and directly at [13]), several images are showing that some dwelling places have been obtained under or inside the fairy chimneys. It seems, as far as it is possible to gain from his pictures that a supporting structure of stones had built to reinforce the chimney (Fig.5). Only a local survey and analysis can tell how many and how old these structures are. For me, a physicist, it is also interesting to model their thermodynamic behavior, such as that of the chimneys in Cappadocia, to see if there are some thermal benefits in using them as houses.
In conclusion, we have seen that a fairy chimneys landscape exists in Peru, where some of the chimneys seem used as dwelling places. Moreover, the documentation of these remarkable structures is due to the activity of a Google Maps user, demonstrating that each user can help in the process of spreading the knowledge of existing cultural landscapes.


Fig.5. This image is adapted from a picture by Max Altamirano Molero, to show the importance of the pictures he collected. Note how the fairy chimneys had been transformed in a dwelling place.


References
1. Frank R. Spellman, Geography for Nongeographers, Government Institutes, 2010
2. www.scienceclarified.com/landforms/Ocean-Basins-to-Volcanoes/Plateau.html
3. How do you make a Hoodoo?, Bryce Canyon National Park,
 www.electronicfieldtrip.org/bryce/lessons/Lesson1.pdf
4. In August 2009, the Dolomites were declared a natural heritage site by UNESCO.
5. Roberto D’Andrea, Il Geosito dei Calanchi di Atri, Tesi di laurea, 2007, Università degli studi “G. d’Annunzio” di Chieti.
6. James Bainbridge, 30 May 2011, BBC, www.bbc.com/travel/feature/20110421-turkeys-land-of-fairy-chimneys
7. Spiro Kostof, Caves of God: Cappadocia and its Churches, Oxford University Press, 1989
8. Lyn Rodley, Cave Monasteries of Byzantine Cappadocia, Cambridge University Press, 2010
9. Thomas Krassmann, Unterirdische Städte in Kappadokien, http://www.mineral-exploration.com/mepub/kaymakli.pdf
10. Rocio Ferrel, ConNuestroPeru, private communication, 2011.
11. Frank Meddens, Rocks in the Landscape: Managing the Inka Agricultural Cycle, The Antiquaries Journal, 86, 2006, pp 36–65
12. Amelia Carolina Sparavigna, Qochas on Andean highlands, Archaeogate, May 5,  2011.
13. Photos by Max Altamirano Molero, in the Google Earth (KML), see also Panoramio, http://www.panoramio.com/user/4345310




Speed of neutrinos and cosmic consequences

Let me report a part of the discussion on the speed of neutrinos by Wikipedia
"In September 2011 the OPERA collaboration released calculations showing velocities of 17-GeV and 28-GeV neutrinos exceeding the speed of light in their experiments. The authors write, "Despite the large significance of the measurement reported here and the stability of the analysis, the potentially great impact of the result motivates the continuation of our studies in order to investigate possible still unknown systematic effects that could explain the observed anomaly." This result had not been detected by previous experiments, and lies in contrast to several others. For instance, photons and neutrinos from SN 1987A were observed to have an agreement in transit time to about 1 part in 450 million, with even this difference being accounted for by light being impeded by the material of the star early in its journey. The OPERA results, in contrast, suggested that neutrinos were traveling faster than light by a factor of 1 in 40,000, i.e. that neutrino speed is 1.0000248(28)c. Had neutrinos from SN 1987A (a supernova, approximately 168,000 light-years from Earth, http://en.wikipedia.org/wiki/SN_1987A) traveled faster than light by this factor, they would have arrived at Earth several years before the photons; this was not observed to be the case. However, neutrinos from the supernova had orders of magnitude less energy than the neutrinos observed in the OPERA experiment, as the authors point out."

Friday, September 23, 2011

Neutrino: fast and furious

Here the news of the day!Neutrinos are faster than light!
http://www.guardian.co.uk/science/2011/sep/23/faster-light-neutrinos
"Scientists at the Opera (Oscillation Project with Emulsion-tRacking Apparatus) experiment in Gran Sasso, Italy, found that beams of neutrinos sent to its detectors from Cern, 730km away in Geneva, arrived earlier than they should have."

Thursday, September 22, 2011

Coherers as “energy catalyzers”

Coherers as “energy catalyzers”

Amelia Carolina Sparavigna
Dipartimento di Fisica,
Politecnico di Torino, Torino, Italy

Abstract: A device defined as an “energy catalyzer”, able to give thermal energy at the expense of electric energy, has aroused a great popular interest. In fact, the confidence on this device does not allow its discussion. Some known features are intriguing, which can therefore become the starting point for a discussion on old coherers and the Branly effect. We could define the coherers as a sort of “energy catalyzers”.

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On Wednesday September 21, 2011, from the news of RAI, the Italian broadcaster, I learned that a new device for energy production was on the way for industrial developments. I had not immediately realized the features of this device, but I memorized the fact that it was based on water, nickel powders and current, that I saw sparkling in the video clip. After searching on the Web, I found that the announced device was the energy catalyzer, E-Cat, under patent request by its inventor, Andrea Rossi. The development of prototypes was due to the work of Rossi and Sergio Focardi, University of Bologna. It seems that they have announced a device able of producing more than 10 kilowatts of heat power, while only consuming a fraction of that. "On January 14, 2011, they gave the Worlds' first public demonstration of a nickel-hydrogen fusion reactor capable of producing a few kilowatts of thermal energy. At its peak, it is capable of generating 15,000 watts with just 400 watts input required. In a following test the same output was achieved but with only 80 watts of continual input" [1]. The item is also reporting that the inventor prefers to invoke a catalyzer process, not to a cold fusion. There are so many Web pages on the E-Cat, that it is impossible to list them, but an exhaustive one is the corresponding Wikipedia item [2]. It is there that we can find the reference to the patent [3], which is about a "method and apparatus for carrying out a highly efficient exothermal reaction between nickel atoms and hydrogen atoms, in a tube, preferably, though not exclusively made of a metal, filled by a nickel powder and heated to a high temperature preferably, though not necessarily, from 150 to 5000°C, by injecting hydrogen into said metal tube said nickel powder being pressurized, preferably, though not necessarily, to a pressure from 2 to 20 bars ".


The confidence on this device does not allow its discussion. And in fact, the aim of my paper is not a discussion on E-Cat, but on what the poor information on it suggested me. Some features of the device attracted my interest: they are the metal powders, the high temperatures and the sparks of electricity. In fact I read recently about all these things together in a old book published in 1904, entitled Element of Physics, by Fernando Sanford, professor at the Stanford University, one of the members of the group of scientists who came there to create the pioneer faculty in 1891. In [4], I discussed the experiments of Sanford on the electric photography and the fact that, several years after in 1939, the fringes around the electrically photographed objects had been rediscovered by Semyon Kirlian. Of course the book written by Sanford is quite old, but, in my opinion, it has to be appreciated due to the fact that it is based on the description of experiments. The book is then quite interesting from the point of view of experimental physics and for its history. A chapter is devoted to electric radiation and electric waves. Let us remember that Fernando Sanford was talking of experiments, which, at his times were revolutionizing physics and technology. Reading the book we learn that a new device was used in laboratories, the Coherer (see Fig.1). Let me report the Laboratory Exercise 119 of the book

"Take a glass tube of about a centimeter bore and six or eight centimeters long, fit the ends with corks through which copper wires can be passed, and fill the tube between the corks with brass or iron filings. Thrust copper wires through the corks and into the iron filings until their ends are one or two centimeters apart. Connect these wires in circuit with one or more voltaic cells and a tolerably sensitive galvanometer. The resistance of the filings to the passage of a current should be so great that the galvanometer is slightly, if at all, deflected. Bring an electric machine near, and pass sparks from one discharging knob into one of the wires which enter the tube. The resistance should fall so that the galvanometer is deflected through nearly 90°. This instrument is called a Coherer. The passage of the electric discharge into the small metallic particles in the tube apparently causes them to cling together so that they make better electric contact than before. After your coherer has become sensitive enough to allow the passage of a suitable current, increase its resistance again by tapping gently on the glass and causing the particles to separate. Then move the electric machine to a distance of a few feet from the coherer and turn the handle and cause sparks to pass between the discharging knobs of the machine. If your coherer has been properly adjusted, the galvanometer will be deflected again, showing that the resistance of the coherer has been again diminished. By a little care in the adjustment, and by using a sensitive galvanometer, the coherer will respond to a spark at a distance of several yards. ... The Coherer described above is similar to the receiver used in "wireless telegraphy." The Coherer is connected between a battery and a telegraph sounder, and is attached to a long wire or other conductor suspended at some height. A similar conductor is suspended at the sending station, and is connected with the spark gap of the electric machine or induction coil. The oscillations in the receiving conductor are accordingly partly due to resonance, and they are sufficient to lower the resistance of the coherer so that a signal can be made through it. An automatic tapper jars the particles apart, so that the signal is momentary unless the instrument is sensitized by another spark. "



Fig.1. The Coherer in the book written by F. Sanford.



The device described by Sanford is a radio signal detector used in the receivers of wireless telegraphy at the beginning of the twentieth century. The coherer was invented, around 1890, by Édouard Branly [5]. As described by Sanford, it consisted of a tube or capsule containing two electrodes spaced a small distance apart, with metal filings in the space between them. To have the Branly effect, it is necessary a thin resistive layer between the grains, to have an initial high resistance. The effect is not observed with noble metal grains, cleaned from any surface contaminant. The coherer works because the metal particles cling together, that is cohere after being subjected to the radio frequency electricity. This provokes a reduction in the coherer's electrical resistance, which is persistent after the radio signal. To receive another signal, the device needs a de-coherer mechanism, able to tap the coherer, mechanically disturbing the particles and resetting them to the high resistance state. As Wikipedia [5] is telling "Coherence of particles by radio waves is an obscure phenomenon that is not well understood even today", but several recent experiments with metal particles seem to confirm that particles cohere by a micro-weld phenomenon, caused by radio frequency electricity fluxing across the small contact area between particles. This phenomenon is probably involving a tunnelling of charge carriers across an imperfect junction between conductors, as deeply discussed in Ref.6. In fact, in this reference the author is proposing to relate the Branly effect to the induced tunnelling effect first described by François Bardou and Dominique Boosé, asserting then that the effect is mainly governed by an electrical tunnel effect [7].


In the work published in 2001 [7], Bardou and Boosé theoretically proposed that the tunnelling probability of a particle through a potential barrier could be enhanced by striking the particle when the centroid of its wave packet is reflecting on the barrier. This is applied to Branly effect as discussed in [6] in the following way. “In a granular metallic medium microscopic grains are electrically isolated one from the other by a metal oxide nanometric layer ... When a voltage is applied to the medium, electrons are accelerated and they do reflect on the potential barriers. At the time of the reflection, these electrons can be kicked forward or backward by the short electromagnetic pulses present in the external electromagnetic field. … The enhanced transmission induced by the momentum transfer produces an increased electrical current, that for some events become large enough to permit a local heating in the metal grains thanks to the Joule effect. Eventually a welding of the grains can occur and when a percolation path has formed the electrical resistance of the medium drops down going from an exponential dependence on the applied voltage to a linear one”. Reference 6 is also reporting that Auerbach demonstrated in 1898 that a coherer could be made conducting by an acoustic excitation in the audible range of the spectrum. According to [6], this means that acoustical wave, by giving vibrations to tunnel barriers between the metallic grains, could be responsible of an induced tunnelling.


Let us also consider the recent experiments with particle coherers by Falcon et al. [8]. They reported on observations of the electrical transport within a chain of metallic beads, which were slightly oxidised. As the applied current is increased, a transition from an insulating to a conductive state is observed. The authors are proposing that the transition comes from an electro-thermal coupling, at the micro-contacts between each bead. Due to these contacts, the current flows through them, generating a high local heating. This heating increases the local contact areas, enhancing the conduction. This current-induced temperature rise, up to 1050°C, results in the micro-soldering of the contact points, even for low voltages.


If we define an “energy catalyzer” as a device able to produce change in, or transform energy, the coherer acts in such a manner, where the catalyst is an electromagnetic pulse. Let us hope that as soon as possible, an open report on E-Cat is published, in order to understand the role of hydrogen in it. In this device, is any tunnelling present? Is it there a tunnelling able to give a fusion of nickel and hydrogen to have copper in a proton capture as told in [9]? Is there any kicking mechanism? What we find in [9] is that the paper is just reporting the results “obtained with a process and apparatus not described here (in [9]) in detail and protected by patent in 90 countries, consisting of a system whose heat output is up to hundred times the electric energy input. As a consequence, the principle of the conservation of energy ensures that processes involving other energy forms are occurring in our apparatus”. And in the conservation of energy we trust.


References

1. http://peswiki.com/index.php/Directory:Andrea_A._Rossi_Cold_Fusion_Generator

2. http://en.wikipedia.org/wiki/Energy_Catalyzer

3. http://www.wipo.int/pctdb/en/wo.jsp?IA=IT2008000532&DISPLAY=DESC

4. A.C. Sparavigna, Fernando Sanford and the "Kirlian effect", arXiv:1105.1266v1 [physics.pop-ph], http://arxiv.org/ftp/arxiv/papers/1105/1105.1266.pdf

5. http://en.wikipedia.org/wiki/Coherer

6. C. Hirlimann, Understanding the Branly effect, arXiv:cond-mat/0703495v1 [cond-mat.mtrl-sci], http://arxiv.org/ftp/cond-mat/papers/0703/0703495.pdf

7. D. Boosé and F. Bardou, A quantum evaporation effect, Europhys. Lett., 53, 1-7 (2001).

8. E. Falcon, B. Castaing, and M. Creyssels, Nonlinear electrical conductivity in a 1D granular medium, The European Physical Journal B, 38, 475-483 (2004)

9. S. Focardi and A. Rossi, A new energy source from nuclear fusion, http://www.lenr-canr.org/acrobat/FocardiSanewenergy.pdf

Wednesday, September 7, 2011

Magnetic scan without magnets

Magnetic scans with a tiny magnet, by Michael Schirber
discussion of the paper entitled Near-Zero-Field Nuclear Magnetic Resonance by M. P. Ledbetter, T. Theis, J. W. Blanchard, H. Ring, P. Ganssle, S. Appelt, B. Blümich, A. Pines, and D. Budker
Phys. Rev. Lett. 107, 107601 (Published September 1, 2011)
"Nuclear magnetic resonance is a powerful technique for analyzing molecular structure in biology, medicine, and materials science. Conventionally, it calls for huge magnets to align nuclear spins and to detect them with high sensitivity, but recent work has demonstrated that similar analysis can be done without a magnetic field. The problem with this zero-field technique is that it can’t unambiguously identify molecules. Now, in a paper in Physical Review Letters, Micah Ledbetter of the University of California, Berkeley, and his collaborators address this limitation, showing that a very small magnetic field can provide extra signatures for chemical discrimination."
http://physics.aps.org/synopsis-for/10.1103/PhysRevLett.107.107601

Tuesday, August 30, 2011

Concrete in the Great Pyramids

Did the Great Pyramids' builders use concrete? 
This is the question we can find in the article by Colin Nickerson on New York Times.
http://www.nytimes.com/2008/04/23/world/africa/23iht-pyramid.1.12259608.html
"It is a theory that gives indigestion to mainstream archaeologists. Namely, that some of the immense blocks of the Great Pyramids of Egypt might have been cast from synthetic material - the world's first concrete - not just carved whole from quarries and lugged into place by armies of toilers. Such an innovation would have saved millions of man-hours of grunting and heaving in construction of the enigmatic edifices on the Giza Plateau."
See also: 
Revisiting the construction of pyramids

Wednesday, August 3, 2011

Objeto del antiguo Egipto sería el primer transportador en el mundo

"Un objeto hallado en una tumba egipcia hace más de 100 años sería el primer transportador, función que finalmente se plante tras un largo misterio entre los arqueólogos sobre su utilidad según informa la revista New Scientist."

Connuestroperu Objeto del antiguo Egipto sería el primer transportador en el mundo

Tuesday, August 2, 2011

Toshka Lakes from space

The decreasing level of Toshka Lakes seen from space
Amelia Carolina Sparavigna,   Dipartimento di Fisica, Politecnico di Torino
http://arxiv.org/abs/1107.4430

Toshka Lakes are lakes recently formed in the Sahara Desert of Egypt, by the water of the Nile,  conveyed from the Nasser Lake through a canal in the Toshka Depression. From space, astronauts noticed the growing of a first lake, the easternmost one, in 1998. Then additional lakes grew in succession due west, the westernmost one between 2000 and 2001. In fact, sources of precious information on Toshka Lakes are the pictures takes by the crews of space missions and the satellite imagery. They show that, from 2006, the lakes started shrinking. A set of recent images displays that the surface of the easternmost lake is strongly reduced. 


Toshka Lakes is the name given to the lakes, quite recently formed, in the Sahara Desert of  Egypt. These new lakes are endorheic, that is, the water can never flow out this region toward the sea. They are near the Nasser Lake (see the map in Fig.1), the huge lake created by the Aswan High Dam, built in 1964-1968. As Wikipedia is reporting [1], in 1978, Egypt began to build the Sadat Canal, originating from the Lake Nasser and passing through the Wadi Toshka, to allow the water, when it is overflowing a specific level, to be drained off to flood a depression located at the south end of a desert limestone plateau. This is the Toshka Depression. In fact, the Egyptian government decided to undertake a development project of the surrounding region, known as the "New Valley Project". The project intends to extend this waterway till the Kharga oasis.

Fig.1 Toshka Lakes are lakes recently formed in the Sahara Desert of Egypt. They are near the Nasser Lake, the huge lake was created by the Aswan High Dam, built in 1964-1968. The water is flowing in the Sadat Canal, pumped in the Toshka Depression, when it is overflowing a specific level in the Lake Nasser. The image has been adapted from the Google Maps. 


 It was in late 1990s [1] that the water started flowing in the canal. This waterway, feeding the depression with the water from Nile, was prepared in order to reduce the water losses. This water, in order to flow the Sadat Canal needs a pumping station, which is situated north of Abu Simbel.  From space, astronauts noticed the growing of a first lake, the easternmost one, in November 1998 [1]. They saw the other lakes grown in succession westward, the westernmost lake between September 2000 and March 2001. A public source of information on Toshka Lakes is in fact in the pictures taken by the crews of space missions. Starting from 2006, the images show that the lakes started shrinking, because of a reduction of water supply [3]. One of the lakes dried out. As reported in [3], the flooding of the Toshka Depression had created the four wide lakes, with their maximum surface area in 2002, of ca 1,500 km^2 , having about 5 × 10^9 m^3 of water. Some of the water evaporated and some recharges the underlying aquifer [3]. At the beginning of the
flooding, the fauna and flora of Nile invaded the Toshka valley [3], with a resultant very rich  population of fishes. But, unfortunately, the water supply reduced. The western-most lake shows a rapidly increasing salinity. As the researches are observing, the zooplankton reacts to the increase of salinity by a striking impoverishment [3]. The life in the lake started to decline.  A publication [4] estimated the loss of water from the lakes using remote sensing and GIS, collecting a set of images and processing them to show the aerial extend shrinkage of these lakes from 2002 up to 2007. By means of a spatial analysis of bathymetry in a digital elevation model, the authors found that the loss rate is around 2.5 m/year. They noted that the lakes stored around 25.26 billion cubic meters of water in 2002, but in 2006 the stored water was reduced to 12.57 billion cubic. The authors conclude that the location of these lakes in such hyper-arid zone is
responsible for a high loss rate, mainly caused by the evaporation, because they found the  percolation of water through the ground quite limited. They say that “It is strongly recommended that measures must be taken to maximize the benefits of these huge, exceptional water resources before totally lost via evaporation. Additionally, geo-environmental problems are likely to arise  from the concentration of salts when the lakes dry up”.


 Fig.2 The "NASA Earth Observatory" allows to see the evolution from 2001 to 2005, of the western Toshka Lakes. In the upper image, we have a record of the lakes as soon as they formed. But in 2005, the water level was strongly reduced.  

Let us see what happened by means of the NASA satellite imagery. The "NASA Earth  Observatory" allow us to see the evolution of the western Toshka Lakes (see Fig.2). In the upper image, we have a figure of the lakes as soon as they formed, 2001. But in 2005, the water level was strongly reduced. In Fig.3, the "NASA Earth Observatory" dated 2005 is compared with an image that we can obtain (on date July 21, 2011) from Google Maps. It is not possible for the author to tell when the Google image had been recorded. But, surely it is more recent, because we see a further reduction of the surfaces of the lakes.



 Fig.3 The "NASA Earth Observatory" of the western Toshka Lakes in 2005 (upper panel) is compared with an image from Google Maps (downloaded July 21, 2011). It is not possible for the  author to tell when the image of the lower panel had been recorded. But, surely it is more recent. We can see a further reduction of water in the lakes. 

Let us note that reference [4] is dated 2007. But what is the current situation of the lakes?
Let us try to answer using NASA images again, and in particular, those of the easternmost  Toshka Lake. In 2005, it was as shown in upper panel of Fig.4, as provided by the "Gateway to Astronaut Photography of Earth". The original image has been enhanced and rotated to compare it with that provided the Google Maps, displayed in the lower panel of Fig.4. As told for Fig.3, it is not possible for me to date the Google image; surely after 2005, because comparing the images, we note that the surface of the lake had shrunk.

 
Fig.4 The easternmost Toshka Lake in 2005, as provided by the "Gateway to Astronaut Photography of Earth", is shown in the upper panel. The original image has been enhanced and rotated to compare it with that provided (downloaded July 21, 2011) by the Google Maps, displayed in the lower panel.  Note that, it is not possible for me to date the Google image. I can only tell thta it is surely after 2005, because comparing the  images, we note that the surface of the lake had shrunk.    

But the "Gateway to Astronaut Photography of Earth" has a set of images of March 31, 2011,  quite recent then, that allowed me to create a composite map of the current aspect of the lake. The  map is proposed in Fig.5. This map had been rotated and enhanced as discussed in Ref. 5 (the image processing proposed in [5] has interesting applications in archaeology, see [6]). The processed images have so many details that we can use them to see the evolution of the lake. This is proposed in Fig.6, where we see a part of the lake, as it evolved from 2005 to March 31, 2011. In this figure we pass from the image dated 2005, to that of 2011, through that from Google Maps, of unknown date. This part of the easternmost lake was large in 2005, shrinking between 2005 and 2011, and reduced to one half the original in 2011, as it can be seen in Figure 7, where the superposition of the two NASA images, of 2005 and 2011, is proposed. We see the surface of the lake strongly decreased.

 
Fig.5 A set of images from the "Gateway to Astronaut Photography of Earth" dated, March 31, 2011, allows to create a composite map of the current aspect of the easternmost lake. This map had been rotated and enhanced as discussed in Ref. 5. The processed image has so many details useful for a comparison with the images in Fig.4.


Fig.6. From the image by the "Gateway to Astronaut Photography of Earth" dated 2005 (up-left), to that of March 31, 2011 (down-right), passing through that from Google Maps (up-right/down-left). The two images labelled with a question mark, are the same. The question mark means that the year when it was recorded is unknown to the author. We have the evolution of a part of the easternmost lake that was large in 2005 shrinking between 2005 and 2011, and reduced to one half the original part in 2011. The surface of the lake has dramatically decreased.  


Fig.7. Superposition of the two NASA images, of 2005 and 2011, of Fig.6, proposed to help the reader in the comparison. 


Let me continue with a little bit of history. Egypt had already lived a similar situation, but on a  longer period and more than two thousand years ago. In Egypt there are several lakes; one is the Lake Moeris, an ancient saltwater lake in the northwest of the Faiyum Oasis. During the prehistory, the lake had freshwaters due to the high flood of Nile. From the XII Dynasty, in 2300 BC, the natural waterway from the river to the lake was widened and deepened to make a canal which is now known as the Bahr Yussef, "the waterway of Joseph" [7]. This canal served for the purpose to control the flooding of the river and help in irrigating the surrounding area. Moreover, the kings of the twelfth dynasty used the water of the natural lake of Faiyum in the dry periods. In fact these kings transformed the lake into a huge water reservoir, giving the impression that the lake was an artificial excavation, as reported by Pliny the Elder. He is writing, when discussing
the pyramids in his book [8], that two of them are “in the place where Lake Mœris was  excavated, an immense artificial piece of water, cited by the Egyptians among their wondrous and memorable works“ [8]. As the surrounding area changed, since the local branch of the Nile shrank, from about 230 BC, the Bahr Yussef became neglected and Lake Moeris began to dry up, creating a depression in the modern province of Faiyum [7].
As the history is showing, it is undoubtedly necessary for the Toshka Lakes what the researches  in Ref.4 are recommending, that is, to undertake measures to preserve these water resources and avoid the problem of the salinity of soil when the lakes dry up. Perhaps, it is too late.


References
1. Toshka Lakes, Wikipedia, http://en.wikipedia.org/wiki/Toshka_Lakes
2. In fact, it was with the Mercury missions in the early 1960s, that astronauts began to take  pictures of the Earth. The NASA, through its "Gateway to Astronaut Photography of Earth", provides a database with locations, supporting data, and digital images. The images are processed from those coming down from the International Space Station, http://eol.jsc.nasa.gov/. The "NASA Earth Observatory", created in 1999, has the same task. This is considered the principal source of satellite imagery and other scientific information on climate and environment, among the services provided by NASA, for the general public, http://en.wikipedia.org/wiki/NASA_Earth_Observatory, http://earthobservatory.nasa.gov/IOTD/view.php?id=1008
3. Gamal M. El-Shabrawy and Henri J. Dumont, The Toshka Lakes, in, The Nile, Monographiae  Biologicae, 2009, Volume 89, III, 157-162.
4. M. El Bastawesy, S. Arafat and F. Khalaf, Estimation of water loss from Toshka Lakes using  remote sensing and GIS, 10th AGILE International Conference on Geographic Information Science 2007, Aalborg University, Denmark, pp.1-9.
5. Anelia Carolina Sparavigna, Enhancing the Google imagery using a wavelet filter, 8 Sep 2010,  Geophysics (physics.geo-ph); Earth and Planetary Astrophysics (astro-ph.EP), arxiv:1009.1590
6. Amelia Carolina Sparavigna, The satellite archaeological survey of Egypt, 31 May 2011, Geophysics (physics.geo-ph), arXiv:1105.6315
7. http://en.wikipedia.org/wiki/Lake_Moeris
8. Pliny, The Natural History, Translated by John Bostock and H.T. Riley, Henry G. Bohm,
London, 1857

Monday, August 1, 2011

Kha's protractor

Kha was an architect at Deir El-Medina, Egypt, supervisor of some projects completed during the reigns of three kings of the 18th Dynasty (approximately 1440-1350 BC). Buried with his wife Merit, the items of their tomb are exposed at the Egyptian Museum, Torino. The papers at http://arxiv.org/abs/1107.4946 describes some devices of the ancient Egypt masonry (cubits, cords, plumb, levels and squares), that Kha used during his activity. An object among those found in his tomb could be used a protractor.


The figure shows an object from the Kha’s Tomb supposed to be the case of a balance scale, or the scale itself as reported by the corresponding label. In a previous preparation of the items of Kha’s Tomb, it was possible to see the front and back of the object. They are the same, with the same complex decoration.


The tool has a complex decoration, that suggested me the case could be used as a protractor, to determine directions and measure angles. The detail of decoration is shown in the following figure. 


 We see the 16-fold symmetry of a compass rose with 16 leaves as an inner decoration. Outside this rose there is a polygonal line with 18 corners and then 36 sides. In the inner decoration we can see the fraction 1/16 corresponding to one leaf. The Egyptian knew  and used the fractions as the sum of distinct unit fractions. That is, a fraction was written as a sum of fractions, each fraction having a numerator equal to 1 and a denominator equal to a positive  integer. Every positive rational number can be represented by an Egyptian fraction. In this ancient system of calculus, the Eye Of Horus defined the Old Kingdom number one, such as, 1 =  1/2 + 1/4 + 1/8 + 1/16 + 1/32 + 1/64, rounded-off at the six-term. A 1/64 is needed to have the exact value 1. The separated parts of the Eye of Horus were used to write describe the fractions. May be, Kha used the balance case for calculations, or simply as a protractor when he was using a plumb, a level or a scale, to find vertical or equilibrium positions, but also to measure the deviation from vertical or horizontal directions. 
Is there anything we can tell about number 36, the number of corners of the external decoration of the architect’s case? Let us remember that the Egyptians has the Decans, 36 groups of stars which rise in succession from the horizon due to the earth rotation. The rising of each decan marked the beginning of hours of the night. In the ancient Egypt, the decans were used as a sidereal clock beginning by at least the 9th or 10th Dynasty (ca 2100 BC). Probably, the object found in the Kha’s tomb had simply a geometrical decoration, such as that on another object of the tomb, which seems to be a “rose of direction”. 



The use of 1/16 fraction, the coincidence of the number of corners with that of decans, and the fact that the decoration was engraved on the instrument of an architect, suggest me that this object had been used as a protractor instrument with two scales, one based on Egyptian fractions, the other based on decans. Assuming this tool used to evaluate angles, let me show a possible set-up to measure the angle of an inclined plane. Note that the case has a lid. Let us imagine to remove the lid; the case has a perfectly linear side, that can be put on a smooth surface, as shown in the following figure.
 


When the surface is horizontal, using a plumb to have the vertical direction, one of the directions of the rose of the case coincides with the direction of the plumb (the line between leaves 1-16 or 8-9 seems to be perpendicular to the side of the case). If the surface is inclined, the direction of the rose is inclined forming a certain angle with respect to the vertical. This angle has the same value of the angle of the inclined plane.  Geometry originated as a practical science, to measure lengths, surfaces and volumes. In my opinion, Kha could have used his tool, with the contemporary use of a plumb to have a reference direction, to create a set-up able to provide a practical measurement of inclination. The Kha’s protractor could be one of the first devices to measure angles. 

References 
Turin Egyptian Museum: the tomb of Kha 
Deir El Medina: The Painted Tombs, Christine Hobson, Exploring the World of the Pharaohs: A 
complete guide to Ancient Egypt, Thames & Hudson, 1993. 
Building in Egypt; Pharaonic Stone Masonry, Dieter Arnold, Chapter 6, Tools and their 
applications, New York and Oxford, 1991 
E. Robens and R.S.H. Mikhail, The ancient Egyptian balance, Thermochimica Acta, Volume 
82(1), 1 December 1984, Pages 63-80. 7. Egypt Plumb Bobs, Wolfgang Ruecher, Wolf’s Plumb Bob News, Issue 02, Feb.2010, 

Tuesday, July 26, 2011

Longobard Necropolis near the Asti-Cuneo motorway

The largest Longobard necropolis in Italy, having 760 tombs -  and one of the most important in Europe because being of a specific century, the VII -  emerged at Sant'Albano Stura, during the works for the Asti-Cuneo motorway. A great discovery, because of the many tombs have funerary items. The necropolis was discovered in the spring 2009; just today the supervisor of Archaeological Studies, Egle Micheletto, gives the announcement, a few weeks after the conclusion of  excavations.
 http://torino.repubblica.it/cronaca/2011/07/25/news/una_necropoli_longobarda_negli_scavi_della_asti-cuneo-19567203/