Monday, November 26, 2018

The Genoese brothers who disappeared looking for a maritime route to spices in the 13th century


From MaritimeHerald by Svilen Petrov

At the end of the thirteenth century, two Genoese brothers with a musical surname embarked on the adventure, fearsome at the time, of finding an alternative spice route.
His idea was to arrive in India with two galleys and for that, they had the help of Mallorcan sailors but after crossing the Strait of Gibraltar they did not know about them again.
It is possible that they were shipwrecked trying to skirt Africa but there are also those who suggest that their route was to the west, which would have meant opening the door that Christopher Columbus followed.
Those pioneers were called Ugolino and Vandino (or Guido) Vivaldi.

It is frequent that the arrival of Columbus to America in 1492 usually tries to cloud with possible trips of previous navigators.
It is proven that, in fact, some arrived before, as evidenced by archaeological excavations in the Viking site of L’Anse aux Meadows (Newfoundland, Canada) and references to Vinland.
We will not go over the usual argument that it was a very modest settlement (just over half a hundred inhabitants), ephemeral and forgotten.

Other predecessors do not go beyond the mere hypothetical phase, in the case of the so-called prenaut, the sailor who would have informed Columbus of a visit to a new world.
He is often identified too cheerfully with a certain Alonso Sánchez de Huelva, although the name does not appear in documents of the time and, in fact, it was the Inca Garcilaso the first to review it in 1609, in his Royal Comments, from stories he had heard circulated from mouth to mouth as a child.

Finally, there are the sensationalist theories that give truthfulness to mere legends such as Saint Brandán’s or the last Templars – they could not miss, of course – or even go back in time to antiquity to propose alleged trips by Egyptians, Phoenicians, Romans and, in general, any other civilization whose presence on the other side of the Atlantic is sufficiently bizarre.
Counterfeit pieces with hieroglyphic alphabets tend to emerge cyclically.

Voyages of the Ming Dynasty (1368–1644) Treasure Fleet

In that sense, not long ago Erdogan updated the Ottoman claim about it with full conviction and the inevitable map of Piri Reis as a flag despite being proven to have been made in 1513.
And there are also those that point to the Chinese fleet of Zheng.
He, who existed and made seven trips but always sailing towards the southwest, to the Indian coast of Africa and its surroundings; that is, in the opposite direction to America.

On the other hand, the expeditions that really tried to cross the ocean are usually left in the drawer.
Some time ago we talked about an unusual one, which was organized by Abubakari II, king of Mali, anxious to know what was on the other side and that disappeared on the high seas in 1312.
But there were more, like those of the British sailors who sailed from Bristol or the Portuguese from the Azores, in both cases in search of those rich islands that the legends placed in the middle of nowhere (Hy-Brasil, Antilia …).

This drive to unravel the secrets of the Atlantic also included, and despite having worse access, Italian navigators; fundamentally of Genoa, one of the maritime powers of the time, being of that origin the two brothers of whom we spoke at the beginning.
The trip they starred was really prophetic, even though we barely know the details, as we ignore the data about their lives.
We only know that they were engaged in the spice trade, whose negative conjuncture was what spurred them to act.

That bad business started in 1291, when the Mamluk sultan Bahrite Al-Ashraf Khalil snatched San Juan de Acre from the Christians, forcing them to evacuate Tire, Sidon and Beirut and expelling them definitively from the Holy Land.
This was a problem for the caravan routes that came from Asia and, consequently, a drastic reduction of the spice consignments, whose demand skyrocketed in parallel to its price.
We had to look for alternatives and the only one that seemed to avoid passing through Islamic territory was to open a seaway “ad partes Indiae per mare oceanum”.


Several merchants joined to finance two galleys with Tedisio Doria at the helm.
The Doria would finance the Portuguese and Spanish explorations two centuries later and, in fact, in Seville a banker of that family, Francesco, worked, who contributed capital for Columbus’ voyage.
The ships of the Vivaldi were called Allegranza and Sant’Antonio and they carried a total of three hundred sailors plus a couple of Franciscan friars, their pilots being Mallorcan (they climbed on the first scale of the trip, which was in the Balearic Islands).

 Portuguese galley on the way to the Malabar Coast (India), Jan Huygen van Linschoten

We said before that it is unknown what the plan was and what was his itinerary since the main historiographical source for this episode are the Annali that Jacobo Doria (uncle of Tedesio) presented to the authorities of Genoa in 1294.
It says:
“Tedisio d’Oria, Ugolino Vivaldi and a brother of the latter, together with some citizens of Genoa, started an expedition that nobody until then had ever tried.
They equipped two galleys in a splendid way.
After supplying them with supplies, water and other necessities, they sent them on their route, in the month of May, to the Strait of Ceuta so that the galleys could sail through the ocean to India and return with useful merchandise.
The two brothers mentioned above were on the boats in person, and also two Franciscan friars; all of which truly amazed those who witnessed it, as well as those who heard about them.
After the travellers passed through a place called Gozora there was no more news of them.
May God watch over them and bring them back healthy.”

There are other references that are those that bring the name of that brother (Vandino), of which Tedisio says that he did not accompany Ugolino on board and that they indicate that they were carrying food for the very long term: no less than ten years.
The Book of Conosçimiento (a geographical-literary manual written by a Castilian friar in the second half of the 14th century that describes the world from the point of view of a traveler, following the model of Marco Polo ) mentions the Vivaldi saying that they were shipwrecked in the region of Guinea and that the son of Ugolino was found looking for his father.

 Portulan of Angelino Dulcert (1339) showing the island of Lanzarote

Sure enough, that Scion was called Sorleone and had organized a rescue expedition in 1315 by not knowing anything about the two galleys.
And he was not the only one because three years before he had already left, led by Lanceloto Malocello, who decided to look first at the Canary Islands, because an island of the Chinijo archipelago was called (and is still called) Alegranza, like one of the galleys.
Only that on the way he found an island to which he put his name ( Lanzarote ) and liked it so much that he changed plans on the march, staying to live there for two decades until the aborigines rebelled against the Europeans and had to leave.

The region of Guinea was not what we would today understand as such, but the way to call all Black Africa.
The Book of Conosçimiento situates the episode in Magdasor, which could perhaps be Mogadishu (Somalia), taking into account not only the cacophonous resemblance but also that it describes it close to the kingdom of Prester John, traditionally located in the Horn of Africa.
This would mean that the Vivaldi managed to double the Cape of Good Hope and sail north through the Indian Ocean.

 Map of Africa by Abraham Ortellius (16th century) indicating the kingdom of the Preste Juan

Now, the Preste Juan was just a willful legend and also that book has a markedly fantastic tone.
Not to mention that other details written by the friar seem to indicate rather that he is talking about the Atlantic African coast, since the Senegal River, the Mali Empire, are cited, as well as other places, in the case of Senegambia.
Precisely the Gambia River was the scene of a meeting between the Genoese sailor Antoniotto Usodimare (who worked for the Portuguese) and a compatriot who claimed to be a survivor of the Vivaldi crew, although the story of Usodimare reproduces almost point by point the Book of the conosçimiento :

“In the year of 1285, two galleys sailed from the city of Genoa commanded by the brothers Ugolino and Guido Vivaldi ( Hugolinum et Guidum de Vivaldis fratres ) with the purpose of going, on the east ( per Levantum ), to parts of India.
These galleys sailed a lot; but when they entered the sea of Guinea ( mari de Ghinoia), one of the galleys broke his helmet, and could not continue sailing further; the other, however, continued through this sea, until he came to a city in Ethiopia called Menam; They were captured and detained by the inhabitants of this city, who are Christians of Ethiopia, subjects of Prester John.
The city is located by the sea, near the Gion river.
They were so closely detained that none of them managed to return home.”

We see that the year is wrong.
All these assumptions and unknowns did not do but enlarge more and more the legend on that trip, which leads to wonder what defeat could follow the ships and what would be its end.
We have already said that the galley was not the type of ship suitable for navigating the ocean, for having too much length, a thin hull and triangular sails; the oars would not help too much with the huge Atlantic swell.
Thus, things probably never went too far from the coast and this one could betray them.

Since the compass had not yet been invented and they lacked nautical charts of the area to be covered, after passing the Columns of Hercules and making a possible stopover in the Canaries, perhaps they continued sailing parallel to the African coast making sporadic landings.
In this way they were able to reach the mouth of the Senegal River, where at least one of the galleys was wrecked, without knowing in what circumstances (in that area there are great shallows, in one of them the famous frigate Medusa ran aground ) or what happened with the other.


If we let imagination go, there are other alternatives: they were able to circumnavigate Africa, which means that the Portuguese Bartolomé Díaz was advanced almost two hundred years ago – and, if they managed to reach India, Vasco de Gama – to get lost in the Indian Ocean, either on the way back … or do it in the Atlantic prow to America, prefiguring what Columbus would do successfully at the end of the 15th century.

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Sunday, November 25, 2018

The Lofoten islands

This is the first one of the mini series #LifeChangingPlaces that follows people who went to a trip that in some form changed their lives.
My team and I spent 9 days on the magical island formation Lofoten in northern Norway to capture the beauty that changed Chris Burkards whole approach to photography. 

 Lofoten islands with the GeoGarage platform (NHS chart)

 
The Lofoten Islands from Nick Kontostavlakis
Μy last trip to Norway during February, 2017.
The Lofoten Archipelago is spread on the northwest side of Norway, very close to the borders of the Arctic Circle.It is a cluster of small fishing villages and is often called “the Foot of the lynx” because of its shape.
The islands are full of legends, maybe because of their natural beauty and their mysterious landscapes, or maybe because there the Sun either never rises or never sets.
The only thing you can hear is the thousand voices of birds, the wind and the sound of the sea.
That combination of the landscape which comes into view every morning and the sounds of nature is a priceless experience that fills you with energy and inspiration for the whole day, no matter what you have to face. 
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Saturday, November 24, 2018

US NOAA update in the GeoGarage platform

27 nautical raster charts updated
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The first chart of Nantucket and Martha’s Vineyard


Atlantic Neptune, 1776/1781
Given what we know about the (extensive) erosion along the Atlantic side of Cape Cod, it's surprising how little change there is on Nantucket.
Only the westernmost spit, and the reverse-D shaped island between Nantucket and Martha's Vineyard, seems to have eroded away. 
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Friday, November 23, 2018

GPS jamming and spoofing: when good signals go bad

GPS constellation

From DirectionsMag by Diana S. Sinton

The most ubiquitous way that the world intersects with the geospatial domain is through location-enabling technologies such as GPS and other GNSS that power and support transportation, communication, and logistics around the globe.
This component of our invisible infrastructure is deeply embedded into our daily lives in ways we usually don’t think about, apart from when we expect our ability to navigate to be accurate and instantaneously available.
Undermining the systems’ reliability? Messing with the GPS? Them’s fightin’ words.

Still, it’s happening and more frequently.
The 30 or so GPS satellites themselves are not as vulnerable to disruption as the signals that they send out and the units that receive them.
For instance, it might seem like a nice idea to create a quiet zone by having incoming calls, messages, and Wi-Fi blocked in an area, but jamming these signals puts many other systems – like GPS – at collateral risk.
It’s illegal to own, sell, or use a GPS jammer in the United States but that’s not so in many other places.
The devices themselves are produced in large quantities in China and elsewhere, and their low cost (about $100 or less) makes them even more tempting for malfeasants.
Where there’s a will, there’s a way for people to acquire and use these.

 Maritime GPS disruptions have been reported elsewhere, but seem to be particularly common in this part of the world.
Electronic navigation signals from the Saudi Arabian Loran-C system and the Russian Chayka/Loran-C system are available for use across most of this region.


Jamming signals is the simple, but less elegant, approach to GPS signal disruption.
Its more complicated and more sophisticated cousin, GPS spoofing, is also becoming more accessible, both technically and financially.
Spoofing works by sending fake signals to a GPS receiver that mimic the ones that the real satellites send.
Weak signal strength of these false ones was a problem in the past, but new technologies have allowed the signals to become strong enough – and more similar to the real ones – that it is possible to have the receiver begin to follow the false ones over the real ones.
As David Last, a former president of the United Kingdom’s Royal Institute of Navigation, recently said, “Jamming just causes the receiver to die, spoofing causes the receiver to lie.”


Todd Humphries, an engineering professor at the University of Texas at Austin, explains it well in his 2012 TEDx presentation.
In the video he shares footage of how he has made the little blinking blue dot on his cell phone’s map – the universal icon for the “you are here” symbol – start to drift blocks away from his home location where he and his phone are actually sitting still.
Since then, he and his research team have done more than these simple at-home demonstrations.
In 2013, they tested their spoofing technologies on a 200-foot yacht in the Mediterranean (with the full cooperation and awareness of the ship’s crew) and digitally manipulated the ship to adjust its directional course as a “correction” that was in fact a complete misdirection.
The ship’s autopilot simply followed its own protocols to make the adjustment, without any awareness that the incoming signals were bogus.

Reports of satellite navigation problems in the Black Sea
suggest that Russia may be testing a new system for spoofing GPS.
source : NewScientist

Larger ships are just as vulnerable to these manipulations.
In 2017, a tanker ship in the Black Sea had its navigational system indicate that it was suddenly in a completely different and improbable location: at an airport 30 kilometers away from its actual location at sea.
All together about 20 ships were affected by this temporary attack, which is now believed to have been Russians experimenting with new approaches to cybersecurity breaches.
GPS signals are regularly jammed in areas immediately around the Kremlin in Moscow, but this Black Sea trouble was the largest real and successful spoofing effort known to date.

Some GPS spoofers have more innocuous intentions, such as those who would try to fool their fellow Pokémon GO players by faking movements.
But really, there are more ways to cause harm than good with these abilities.
Virginia Tech’s Curtis Zeng and his colleagues have managed to further lower the barriers by creating a successful spoofing system that costs only a few hundred dollars.
With this inexpensive system in place, they were able to insert manipulated, false signals into navigational routes that were being followed by volunteers in a simulated driving situation.
The attacker does not change the original destination, but instead manipulates the user's real-time location (now a “ghost” location) on the map.
The navigation system will recalculate a fake virtual route from the ghost location to the original destination, one that would be physically feasible for the user to travel in the real world.
Ideally, this would not trigger the telltale "re-calculating" warning, depending on whether the ghost location is on or off the original navigation route.
Drivers continue to follow the navigation instructions, but now they are actually on a new route that the attackers planned.

Even more tricky is that Zeng and his colleagues managed to swap in false map layouts to further keep the drivers in the dark.
With these “ghost” maps in place, almost all of the drivers in this study naively continued to follow directions that had been tweaked to arrive at false destinations.
According to Zeng, “Users tend to heavily rely on navigation systems in unfamiliar areas rather than learning the map and planning routes ahead in an old-fashioned way.
It is (already) hard for them to drive, follow navigation instructions, and cross-check the surrounding environment at the same time.
Moreover, few users understand how navigation systems work and how hackers can manipulate them.
Many users have also experienced brief navigation malfunctioning in real life, so a rapid ‘blip’ in the system does not alert them (to any changes having been made).”

Tech-smart people are figuring out how to do this for nefarious reasons and other tech-smart people are working to stop them, or at least give us more chances for better outcomes.
A group of Irish electrical engineers recently documented the ways in which they could successfully achieve multi-frequency spoofed GPS signals with inexpensive and readily available equipment, to show that it could be done (multi-frequency had been thought unachievable) and to continue to keep the conversations active.
Overestimating and underestimating the capacities of the adversaries are both counterproductive activities.

Hacking ships

Efforts with multiple strategies and tactics are underway by researchers, the public sector, and the federal government to combat the problems.
What several of these have in common is that they’re working to have the overall system of navigation be less reliant on GPS signals and their related time stamps alone.
Those atomic-clock-enabled time stamps are considered so reliable that they are counted on for countless processes.
At Clemson University, engineers are experimenting with a technique that regularly samples real GPS signals and tags those signals in a way that confirms their validity.
Other users’ devices can automatically compare the ones issued by Clemson with the ones that their devices are collecting.
This isn’t stopping spoofing from happening, but it is making the end user aware if their signals are being compromised.
Meanwhile, other researchers are taking it a step further and developing ways to correct the compromised signals.
Other approaches being pursued by private companies involve having navigational systems ready to receive signals from alternative sensors, such as mobile phone networks or commercial satellites, when it is detected that the GPS signals have irregularities.
These diverse strategies may not seem coordinated, but one organization that is staying on top of the problem is the Resilient Navigation and Timing Foundation, a group that is involved with the situation on many global fronts.

We’re confronted with jamming and spoofing that can be accomplished successfully by small-time actors building cheap contraptions in their basements, and larger actors, with deeper pockets and expertise, that may be working on behalf of foreign governments.
Really, it’s all part of a bigger problem: that the whole GPS system has too few redundancies and too many potential leaks that can be compromised too readily.
One path being pursued is simply to have more GPS satellites be part of the collection as quickly as possible, and to produce new receivers designed with as many cybersecurity countermeasures as possible.
We celebrate the open GPS system that provides us with such novel and independent ways to leverage location-based goods and services, but it’s clearly been a mixed blessing.

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