Hi! Thank you so much for telling us that fascinating description of that guy! Very, very interesting, not to mention exactly on point. --Dan

On Mar 26, 2015, at 4:09 PM, Landon Curt Noll <mathfun-mail@asthe.com> wrote:

Hello,

During our 2009 Total Solar Eclipse expedition to search for Vulcanoid asteroids we flew into the Enewetak atoll in the Marshall Islands. During our stay I met a native who had used his canoe to visit Enewetak from Bikini: almost 200 nautical miles away.

Through a translator, I was curious how he made the journey. He showed me his craft .. a sort of dugout canoe with an outrigger. He had no GPS, no compass, no radio, no electronics of any kind. Only some dried food, coconuts, some water and stuff that looked like it could be used for fishing. He said he does this run several times a year to visit friends and relatives and to carry news.

I was curious how he made the journey in such a craft without any apparent navigational aide. So I asked him how he knew where to go. The look he gave me was one of "are you that stupid" saying that the direction should be obvious to anyone. :-) When I expressed a child-like ignorance of how to go such a long distance he explained a process of birds, the sun, the stars, waves and listening to surf when he was close, etc.. He explained how to tell if a bird was going a direct route between islands or wondering .. plus a bunch of other stuff I didn't understand in context.

He really knew his star fields! I showed him a star chart of stars down to 6th magnitude. Although our names were different, he definitely knew his was around the sky and seemed to recognize stars on the charts with ease giving me names in his language of a fair number of the brighter stars.

I asked him for directions to places like Ujae (where he was going next, some 240 nautical miles away), Amo, Bikini, Kili, Wotho, etc. He pointed with dead certainty to any atoll/island I could name. I got out my GPS compass and asked him to turn my hand in the direction of an island/atoll. He could repeatedly orient me within about 2 degrees of any atoll/island I could name .. and I suspected some of that error was my not keeping the GPS/arm steady.

He seemed very puzzled that an adult such as myself could grow up not knowing how to navigate on the ocean. He talked about the currents, what the islands were like, where to find water or coconuts when the rain did not fall, etc. I'm still not entirely sure how he did it but he claimed to do all with ease.

I showed him a physical compass. He had seen such things before but dismissed them as "they would only get wet .. they were useless".

BTW: He was impressed with the 2009 eclipse. He said he was going to carry that tale with him through the islands. No doubt he was going to tell jokes about meeting adults who can't find their was around the pacific islands. ;-)

Our translators said this navigators such as this man made a living carrying news and messages between islands.

chongo (Landon Curt Noll -- just back from the 2015 Polar eclipse warming up in Switzerland) /\oo/\

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Absolutely fascinating!! Thanks, Landon! Ok, so Polynesian humans routinely do this kind of navigation, and this skill is not considered to be unusual or rare (among Polynesians). So it should be possible for a computer to emulate it. If you have a clear view of the night sky and an accurate clock (which every computer has), then the problem is trivial, and apparently many toy telescopes today already have the appropriate software built in. So one would have to disallow access to the computer's clock, and kill its night vision. The next question would be how important seeing various birds would be. Let's assume it's helpful, but not dispositive. So we're left with a pretty decent map (people can memorize such things -- e.g., "The Knowledge" of London taxipersons), a day-time camera, and at least a 3-axis motion sensor. In other words, a modern Android phone could use its camera and motion sensors and turn off its communication devices. Just paste a filter over the camera to eliminate the ability to see the night stars. I'm particularly interested if there is enough information in the wave/swell patterns to reliably guide a robot craft across hundreds of miles of ocean. One could incorporate one of those GPS/satellite beacons used by mountain climbers -- disconnected from the rest of the circuitry of the robot, of course -- in order to be able to monitor the robot craft's progress. Given how cheap computers have gotten recently, the entire computer rig -- even including batteries -- could be done for a couple thousand dollars. Put this computer into a very robust model RC sailing craft and this experiment could be done by a high school student who happened to live on the West Coast of the U.S. For example, could such a craft make it to Catalina from Long Beach? Or reproduce the Kon-Tiki voyage from South America. At 04:09 PM 3/26/2015, Landon Curt Noll wrote:

Hello,

...

I heard a recent program on the ability of ancient Polynesians to navigate the Pacific Ocean w/o clocks/longitude or GPS.

Supposedly, the Polynesian navigators use information about waves/swells/etc. to detect the presence & direction of islands over the horizon.

I'm a bit skeptical about this, because unless these skills are relatively easily acquired, anyone with less than a certain critical mass of skills will die, and even partial skills won't be transferred to the next generation. (This is semi-analogous to the spread of a communicable disease, only in this case we _want_ the navigational information/techniques to propagate.)

During our 2009 Total Solar Eclipse expedition to search for Vulcanoid asteroids we flew into the Enewetak atoll in the Marshall Islands. During our stay I met a native who had used his canoe to visit Enewetak from Bikini: almost 200 nautical miles away.

Through a translator, I was curious how he made the journey. He showed me his craft .. a sort of dugout canoe with an outrigger. He had no GPS, no compass, no radio, no electronics of any kind. Only some dried food, coconuts, some water and stuff that looked like it could be used for fishing. He said he does this run several times a year to visit friends and relatives and to carry news.

I was curious how he made the journey in such a craft without any apparent navigational aide. So I asked him how he knew where to go. The look he gave me was one of "are you that stupid" saying that the direction should be obvious to anyone. :-) When I expressed a child-like ignorance of how to go such a long distance he explained a process of birds, the sun, the stars, waves and listening to surf when he was close, etc.. He explained how to tell if a bird was going a direct route between islands or wondering .. plus a bunch of other stuff I didn't understand in context.

He really knew his star fields! I showed him a star chart of stars down to 6th magnitude. Although our names were different, he definitely knew his was around the sky and seemed to recognize stars on the charts with ease giving me names in his language of a fair number of the brighter stars.

I asked him for directions to places like Ujae (where he was going next, some 240 nautical miles away), Amo, Bikini, Kili, Wotho, etc. He pointed with dead certainty to any atoll/island I could name. I got out my GPS compass and asked him to turn my hand in the direction of an island/atoll. He could repeatedly orient me within about 2 degrees of any atoll/island I could name .. and I suspected some of that error was my not keeping the GPS/arm steady.

He seemed very puzzled that an adult such as myself could grow up not knowing how to navigate on the ocean. He talked about the currents, what the islands were like, where to find water or coconuts when the rain did not fall, etc. I'm still not entirely sure how he did it but he claimed to do all with ease.

I showed him a physical compass. He had seen such things before but dismissed them as "they would only get wet .. they were useless".

BTW: He was impressed with the 2009 eclipse. He said he was going to carry that tale with him through the islands. No doubt he was going to tell jokes about meeting adults who can't find their was around the pacific islands. ;-)

Our translators said this navigators such as this man made a living carrying news and messages between islands.

chongo (Landon Curt Noll -- just back from the 2015 Polar eclipse warming up in Switzerland) /\oo/\