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

Saturday, June 23, 2012

A portrait of Julius Caesar


My image processing based on the Tusculum Bust, Museo Archeologico di Torino.
The Tusculum bust is considered a portrait of Julius Caesar

Friday, June 22, 2012

Alan Turing

Google celebrates the 100th birthday of a computer genius, Alan Mathison Turing (23 June 1912 - 7 June 1954) with a doodle. He is the founder of computer science. He broke the german Enigma-ciphered code.

http://timesofindia.indiatimes.com/tech/news/internet/Alan-Mathison-Turings-100th-birthday-Google-pays-tribute-with-a-doodle/articleshow/14353203.cms

Thursday, June 21, 2012

Silicene

Silicene pops out of the plane - physicsworld.com
"Researchers in Japan say that they have made 2D honeycomb crystals of silicon that resemble the carbon-based material graphene. This is the second potential sighting of the material dubbed "silicene"; the other was reported in April by an independent group in Europe. The Japanese research suggests it may be relatively easy to alter the structure of silicene by changing the substrate on which it is grown – which could allow different versions of silicene to be produced with a range of useful electronic properties. However, not all scientists agree that this latest material is actually silicene."

Tuesday, June 19, 2012

Arles, Turin and Caesar

The heart of the ancient history of Arles, this is what is on show at the Louvre Museum of Paris, until 25 June 2012. The Museum is  hosting an exhibition of spectacular Roman pieces recovered from the bottom of the Rhone! From March 9 to June 25, 2012, the Louvre Museum in Paris

On exhibition fifty of the most spectacular artifacts unearthed by archaeologists: columns and capitals, fragments of statues and reliefs, Roman jewelery, lamps, vases ... These pieces are coming from the museum of Arles, and other pieces from Avignon, Vienne and Turin.
Among the pieces from Turin, you can admire Julius Caesar's bust, unearthed in 1825,  long considered unique, until the discovery in 2007 in Arles of another bust of the Roman politician. At the Louvre, these sculptures will be presented for the first time side by side.


http://www.france.fr/it/arti-e-cultura/evenement/arles-gli-scavi-del-rodano-un-fiume-memoria

   Arles

Torino

Un altro ritratto interessante รจ quello del busto Farnese, a Napoli

 Napoli


Thursday, June 14, 2012

Blackwood and Lovecraft

Of such great powers or beings there may be conceivably a survival... a survival of a hugely remote period when... consciousness was manifested, perhaps, in shapes and forms long since withdrawn before the tide of advancing humanity... forms of which poetry and legend alone have caught a flying memory and called them gods, monsters, mythical beings of all sorts and kinds...

These words written by Algernon Blackwood introduce the The Call of Cthulhu, by H. P. Lovecraft. 

"The most merciful thing in the world, I think, is the inability of the human mind to correlate all its contents. We live on a placid island of ignorance in the midst of black seas of infinity, and it was not meant that we should voyage far. The sciences, each straining in its own direction, have hitherto harmed us little; but some day the piecing together of dissociated knowledge will open up such terrifying vistas of reality, and of our frightful position therein, that we shall either go mad from the revelation or flee from the light into the peace and safety of a new dark age." 

Tuesday, June 12, 2012

Ancient Rainfall, Carved in Stone

"Stalactites grow from cave ceilings not as dull cones but often sporting elegant corrugations. In Physical Review Letters, two Italian researchers now explain these mysterious, wavy patterns using standard fluid mechanics. Their theory shows that the horizontal ripples form because spatially periodic patterns arise in the rate of mineral deposits from the water flowing down the stalactite. Starting from this model, climate scientists might in the future use stalactite surface structure to reconstruct variations in precipitation patterns over tens of thousands of years."
Ancient Rainfall, Carved in Stone

Friday, June 1, 2012

NGC 891

Another superb image at http://apod.nasa.gov/apod/ap120526.html
" This sharp cosmic portrait features NGC 891. .. At first glance, it has a flat, thin, galactic disk and a central bulge cut along the middle by regions of darkobscuring dust. The combined image data also reveal the galaxy's young blue star clusters and telltale pinkish star forming regions. And remarkably apparent in NGC 891's edge-on presentation are filaments of dust that extend hundreds of light-years above and below the center line. The dust has likely been blown out of the disk by supernova explosions or intense star formation activity. "

Here the NASA image after processing with AstroFracTool and Iris


Transit of Mercury

Very beautiful image at http://apod.nasa.gov/apod/ap120527.html Image Credit: SOHO - EIT Consortium, NASA
"The diminutive disk of Mercury, the solar system's innermost planet, spent about five hours crossing in front of the enormous solar disk in 2003 ... the horizon was certainly no problemfor the sun-staring SOHO spacecraft. Seen as a dark spot, Mercury progresses from left to right (top panel to bottom) in these four images from SOHO's extreme ultraviolet camera. The panels' false-colors correspond to different wavelengths in the extreme ultraviolet which highlight regions above the Sun's visible surface."

Here the image from NASA after processing with IRIS




Transit of Venus

"The next transit of Venus, where Venus appears as a dark spot in front of the Sun, will begin at 22:09 UTC on 5 June 2012, and will finish at 04:49 UTC on 6 June.[1] Depending on the position of the observer, the exact times can vary by up to ±7 minutes. Transits of Venus occur in pairs that are eight years apart: the previous transit was in June 2004, and the next pair of transits will occur in December 2117 and December 2125." from Wikipedia

Aristarchus proposed to measure the distance to the Sun using parallax. This approach based on the geometric principles of parallax last for two thousands of years, until Edmond Halley in 1716 proposed to observe the transit of Venus. The use of Venus transits gave an estimate of 1.53×10^13 cm, 2.6% above the currently accepted value, that of l.49 × 10^13 cm. More recently, in 1910, the parallax was measured using the asteroid Eros that passed much closer to Earth than Venus. A transit of Venus happens when this planet passes directly between the Sun and Earth, appearing as a small black disk moving across the Sun bright disk. The duration of such transits is usually measured in hours.
Read more "Two amateur astronomers at Berkeley", at http://arxiv.org/abs/1202.0950

Tuesday, May 8, 2012

An ancient rangefinder (Roman Dodecahedron)

According to Wikipedia, "a rangefinder is a device that measures distance from the observer to a target, for the purposes of surveying, determining focus in photography, or accurately aiming a weapon. Some devices use active methods to measure (such as sonar, laser, or radar); others measure distance using trigonometry (stadiametric rangefinders and parallax, or coincidence rangefinders). These methodologies use a set of known information, usually distances or target sizes, to make the measurement, and have been in regular use since the 18th century".
 It could be surprising, but probably the Roman Army had a rangefinder. It was the Roman Dodecahedron (I have already discussed it in some posts and papers: on arXiv, where I am explaining how  it can be used for measuring distance as a rangefinder, http://arxiv.org/abs/1204.6497 ).
For me, those dodecahedrons having a structure with holes of different sizes, are military instruments to evaluate distances for ballistics. It is simple to use. Of course, later, during the Middle Age, different instruments had been developed for surveying: the dodecahedron was of the Roman Army, and, probably, its use lost after the collpase of the Empire. See also "Ancient and Modern Rangefinders", on arXiv, http://arxiv.org/abs/1205.2078 and on SCIRP  http://www.scirp.org/journal/PaperInformation.aspx?PaperID=23245