The paper is basically like this (spoiler alert):

“Some random user on Reddit posted a picture claiming that this is the longest straight line path on water possible on the Earth. We implemented a smart algorithm to solve this problem, found the elevation data, ran our algorithm... yes, that random user was right. Also, here's the longest path on land.”

Thanks, I really enjoyed reading it, even though I hoped that they would disprove the original claim!

Edit: here are the gcmap links to the two paths: sea [1], land [2].

[1]: http://www.gcmap.com/mapui?P=25%B017%27N+66%B040%27E-58%B037...

[2]: http://www.gcmap.com/mapui?P=24%B033%27N+118%B038%27E-37%B02...

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cubefox a day ago | parent | next [-]

They only identify the Reddit user as "kepleronlyknows", but in the Reddit thread [1] he links to his video visualization [2], where his user name is Patrick Anderson.

Before he made the video visualization using Google Earth, he actually went to the library and used a string on a real globe. [3]

1: https://www.reddit.com/r/MapPorn/comments/15mwai/the_longest...

2: http://www.youtube.com/watch?v=VpQwuGueeoA

3: https://imgur.com/a/great-circle-2hYFM

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alok-g a day ago | parent | prev | next [-]

Adding: The two paths respectively are about 80% and 28% of the earth's circumference.

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kromokromo a day ago | parent | prev | next [-]

Kudos to whoever built tiled clouds background on the gcmap site.

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comrade1234 a day ago | parent | prev | next [-]

I opened Apple Maps in globe mode and I still have trouble visualizing the water path.

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pdpi a day ago | parent | next [-]

Does it help to point out that the water path looks suspiciously like the day/night line on a map?

Like this: https://svs.gsfc.nasa.gov/5477/

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newtwentysix a day ago | parent [-]

yes!! why is that ? :)

	▲	yorwba a day ago \| parent [-]
		The day/light line is a great circle. The "straight line paths" are great-circle segments.

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srean a day ago | parent | prev | next [-]

It's going South and then trying to close the loop from behind. It gets interrupted by land before the loop closes.

Hope it makes sense.

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turbocon a day ago | parent | prev [-]

Open the linked paper and scroll down, they have images of the path on a globe as well as the flat map view.

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paganel 13 hours ago | parent | prev [-]

The Portugal to (approximately) Macao one is quite interesting, thanks for the links!