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

Showing posts with label Google Earth. Show all posts
Showing posts with label Google Earth. Show all posts

Friday, February 1, 2019

Come fare i profili d'elevazione con Google Earth

Aprite Google Earth e scegliete il posto. Prendiamo il Meteor Crater.


Prendete il "righello". E' il tool che vedete in alto a destra del "pianeta".


Tracciate la retta col mouse e salvate la linea costruita con un nome.


Andate in alto su "modifica" e selezionate "mostra profilo elevazione".
Eccolo!


Monday, December 31, 2018

Huge, Unseen Operation Behind the Accuracy of Google Maps

GREG MILLER (SCIENCE)
12.08.1406:45 AM
THE HUGE, UNSEEN OPERATION BEHIND THE ACCURACY OF GOOGLE MAPS
https://www.wired.com/2014/12/google-maps-ground-truth/

"Other algorithms extract building footprints and heights from satellite and aerial imagery. The majority of buildings in the U.S. are now on Google Maps. For landmarks like Seattle's Space Needle, computer vision techniques extract detailed 3D models (see below). Google has said that its recent acquisition of Skybox, the high-resolution satellite imagery company, at least initially, is to improve the accuracy of its maps."

Saturday, February 1, 2014

stone circle - 2 - Jordan

Stone circles in Jordan.
Syrian desert.


Stone circle and desert kite

Stone circle and desert kite in Jordan

Stone circle - Jordan - 1


A stone circle in Jordan

About Jordan and the Syrian Desert, see also:

Desert kites - 1


The Syrian Desert is an arid land of south-western Asia, extending from the northern Arabian Peninsula to the eastern Jordan, southern Syria, and western Iraq, largely covered by lava fields. Considered in the past as a barrier between Levant and Mesopotamia, it is now crossed by several routes and pipelines. This desert possesses two volcanic regions. One is the Jabal al-Druze, in the As-Suwayda Governorate. The other field is that of the Harrat Ash Shaam.

When we observe this desert from space, we discover that this harsh environment was probably quite populated in ancient times. We can conclude this fact from some huge stone structures, the "desert kites", that can be easily seen in the images recorded by satellites. These structures were firstly observed by pilots of the Royal Air Force in the 1920s, flying over the desert. These pilots named them "kites", because these lines reminded of kites used by children to play, but in fact they are huge hunting traps.

We usually imagine our ancestors, before they settle down, as people simply hunting and gathering for food, but this is not true. The "desert kites" are the remains of an ancient hunting technique based on stone-walled traps, the construction of which surely involved several people for long times. The desert kites were used to push large herds of animals into some enclosures, or, in the worse case, to fall off from steep cliff edges. The simplest structure of a desert kite has a triangular shape, consisting of two long, low walls built of stones and arranged in a V-shape, like a  funnel, ending as a corral. Hunters pushed the game between the walls, trapping then the animals into the end of the structure. It is usually considered that animals were slaughtered “en masse”.

Typically, a desert kite possesses two, three or more small circular enclosures on the edge of its corral. Some ancient rock art images show these hunting traps, depicting the role of the 'walls' of the kites. Let us note that these walls are low and then not able to stop any game. In fact, the walls are not walls at all: they are the basements, in the rocky harraat, where stick some poles and build a fence with branches. These structures create a visual effect as a barrier for the animals.



"Kite" rock-drawing from Jordan,  G.L. Harding: The Cairn of Hani, Antiquity 28,1954:pp 165-7
(2007-02-22) In 1951, Harding discovered a burial cairn with Safaitic inscriptions. On one of the stones was scratched a hunting scane.The cairn is located in the heart of the 'Kite' area,there is no doubt that the drawing depicts a scane of the gazelles being hunted in such a' Kite'.

References
23 June 2011,  http://arxiv.org/abs/1106.4665 , http://arxiv.org/pdf/1106.4665v1.pdf
February 2009, Khaybar Desert Kites, Vanja Janežic
alsahra.org/wp-content/uploads/2009/02/khaybar-desert-kites.pdf
http://www.megalithic.co.uk/article.php?sid=2146412866

Thursday, August 22, 2013

Moving sand dunes on Mars

Moving Sand Dunes on Mars, by Amelia Carolina Sparavigna, Department of Applied Science and Technology, Politecnico di Torino, Torino, Italy

Abstract: It was recently announced that the sand dunes on Mars can move. This important result was obtained by means of the High Resolution Imaging Science Experiment (HiRISE), the camera onboard the Mars Reconnaissance Orbiter. The images, recorded three years apart, of the dunes in the Nili Patera caldera show that they move. Here we compare an image HiRISE of 2007 with an image of 1999 recorded by the Mars Global Surveyor. Therefore, with the help of Gimp, the GNU image processing software to enhance the images, we can see and measure the motion of the dunes during a longer period of time.

A dune on Mars which is moving. In the Nili Patera caldera.
199 on the left, 2007 on the right


More details and article at:


Sunday, August 11, 2013

From Google Earth to Tatooine

Today (11 August 2013)  I found this article entitled "Star Wars home of Anakin Skywalker threatened by dune" http://www.bbc.co.uk/news/science-environment-23375344
It is told that "Sand dunes migrating over the Tunisian desert are poised to bury a famous Star Wars film set. The buildings of the fictional city Mos Espa featured in The Phantom Menace, "Episode I" of the Jedi saga. Sited on the planet Tatooine, this was the home of the young Anakin Skywalker ... Scientists have used the dwellings as a fixed geographic reference to measure the migration of giant wind-blown crescent-shaped dunes, or barchans. They have published details in the journal Geomorphology." The paper is in press, and you can see it at  http://www.sciencedirect.com/science/article/pii/S0169555X13003486
BBC continues "Ralph Lorenz, from Johns Hopkins University, ...  visited the Mos Espa site in 2009, and noted that part of a nearby set used in Star Wars Episode IV: A New Hope had already been overrun. Using satellite images of the site, they were able to determine the speed of dune movement, which is approaching the buildings once inhabited by such luminaries as Anakin, his slave owner Watto, and rival podracer Sebulba".
Before these "Dunes on the planet Tatooine",  on 4 January 2013 it was published  my "Moving Dunes on the Google Earth", as you can find at http://arxiv.org/abs/1301.1290, where I showed how to use the time series of the Google Earth to estimate the motion of the barchans. I used the barchans in Peru. I have also  discussed how to use reference points and adjust the Google images to have a "movie".
It seems that the authors of "Dunes on planet Tatooine: Observation of barchan migration at the Star Wars film set in Tunisia" do not know my "Moving dunes on the Google Earth" because my paper is not cited.
Therefore I cite myself!

And show you a "movie" of the barchan which is threatening Luke Skywalker's home.








Moving sand dunes on the Google Earth

"Moving dunes on the Google Earth" is my paper on arXiv, published 4 January 2013. It shows how using GH time series you can see the motion of dunes. Here an example.


To see a movie, please visit Moving sand dunes ... post

Thursday, September 27, 2012

Airplane on water


Airplane on water, Rio de Janeiro, Google Maps


Google Earth


Silbury Hill


Silbury Hill on Google Earth

More info
A possible role of Alpha Crucis in the astronomical landscape of Silbury Hill