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Longest Straight Line Paths on Water or Land on the Earth (2018)

arxiv.org

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Re: Longest Straight Line Paths on Water or Land on the Earth (2018)

#51

Post by madcaptenor »

1718627440 wrote: post #42
madcaptenor wrote: post #24

Earlier quoted context omitted.

Over water, probably something like the entire 60th parallel south. Over land, I think you want to start near the westernmost point of the African continent and thread the needle of the Isthmus of Suez, and stay south of the Caspian Sea. At least in the projection gcmap.com uses (plate carree - essentially the x-coordinate and y-coordinate are just raw longitude and latitude), this keeps you south of Lake Baikal and…

> Of course this depends on the projection you use! But if you do not believe in a globe how do you understand projections?

Well, they wouldn't call it a "projection", but whatever drawing of the map they use.

Re: Longest Straight Line Paths on Water or Land on the Earth (2018)

#52

Post by alok-g »

ventana wrote: post #2

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 th…

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

Re: Longest Straight Line Paths on Water or Land on the Earth (2018)

#53

Post by kromokromo »

ventana wrote: post #2

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 th…

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

Re: Longest Straight Line Paths on Water or Land on the Earth (2018)

#54

Post by rotringlvr »

gus_massa wrote: post #45
rotringlvr wrote: post #32

Before I opened the solution, I knew it had to pass through the beagle straight. It is the only choke point separating the largest oceans, about both their empties areas, the far south. I guess my biggest surprise is that there is a straight line through the Beagle straight.

Beagle Channel is very narrow and has islands both on the north and the south. This path goes thought the Drake Passage that is south of the islands that are south of the Beagle Channel. The Drake Passage is very wide.

Right, the Drake.

Re: Longest Straight Line Paths on Water or Land on the Earth (2018)

#55

Post by testing22321 »

OscarCunningham wrote: post #48
khaled_ismaeel wrote: post #31

Earlier quoted context omitted.

It seems like that path crosses the Suez canal. I think it's fair that bridges and/or tunnels don't count.

The one they give also crosses numerous rivers and lakes. For the strict version of the challenge where you literally can't cross water it's likely that the best solution is across Antarctica. Guaranteed by temperature to contain no water whatsoever.

> Guaranteed by temperature to contain no water whatsoever.

Depends on where and when.

Plenty of puddles form around the bases in summer.

Re: Longest Straight Line Paths on Water or Land on the Earth (2018)

#56

Post by 1718627440 »

madcaptenor wrote: post #51
1718627440 wrote: post #42

Earlier quoted context omitted.

> Of course this depends on the projection you use! But if you do not believe in a globe how do you understand projections?

Well, they wouldn't call it a "projection", but whatever drawing of the map they use.

Yeah, but how do they explain, that the same world looks different, e.g. having different distances and angles depending on the map "type"? This is kind of important for traveling, navigating or measuring the size of the property you own.

Re: Longest Straight Line Paths on Water or Land on the Earth (2018)

#57

Post by phinnaeus »

1718627440 wrote: post #56
madcaptenor wrote: post #51

Earlier quoted context omitted.

Well, they wouldn't call it a "projection", but whatever drawing of the map they use.

Yeah, but how do they explain, that the same world looks different, e.g. having different distances and angles depending on the map "type"? This is kind of important for traveling, navigating or measuring the size of the property you own.

They’re flat earthers, they either have no explanation or a completely bogus explanation. Certainly don’t look for any semblance of reason. They just invent whatever to try and feel like they have some secret knowledge.

Re: Longest Straight Line Paths on Water or Land on the Earth (2018)

#58

Post by globular-toast »

gcanyon wrote: post #43

I know the globe is unintuitive (it still blows my mind that Muslims in New York City face roughly northeast to point toward Mecca) but it still seems bizarre that the water route can start near the arctic circle, cross the Pacific ocean, nearly touch Antarctica, cross the Atlantic ocean, and cross the Indian ocean to end well north of the equator and still travel only 80% of the way around the globe. This view of th…

> it still blows my mind that Muslims in New York City face roughly northeast to point toward Mecca

It never occurred to me they would face the shortest distance to Mecca. I've looked it up and apparently it's a point of contention in North America, although the great circle seems to be standard. Interestingly there are landmasses around the antipode of Mecca, which means your direction would vary wildly as you travel around.

Re: Longest Straight Line Paths on Water or Land on the Earth (2018)

#59

Post by SamBam »

gcanyon wrote: post #43

I know the globe is unintuitive (it still blows my mind that Muslims in New York City face roughly northeast to point toward Mecca) but it still seems bizarre that the water route can start near the arctic circle, cross the Pacific ocean, nearly touch Antarctica, cross the Atlantic ocean, and cross the Indian ocean to end well north of the equator and still travel only 80% of the way around the globe. This view of th…

If you're in New York and you look due East across the Atlantic, what country are you looking at?

Most people would assume Portugal.

Nope, you're looking (over the curve of the earth, of course), at Morocco. Look just a tiny bit to the south and you're looking at the rest of West Africa. Look Southwest and you're looking at Australia, or even Brazil.

Re: Longest Straight Line Paths on Water or Land on the Earth (2018)

#60

Post by 1718627440 »

phinnaeus wrote: post #57
1718627440 wrote: post #56

Earlier quoted context omitted.

Yeah, but how do they explain, that the same world looks different, e.g. having different distances and angles depending on the map "type"? This is kind of important for traveling, navigating or measuring the size of the property you own.

They’re flat earthers, they either have no explanation or a completely bogus explanation. Certainly don’t look for any semblance of reason. They just invent whatever to try and feel like they have some secret knowledge.

I'm just curious. I think they still believe to have a consistent worldview themself, as every human does. My question was more regarding their self-understanding and less the kind-of "marketing" they throw at outsiders.
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