Rainbow in curved ocean

November 30, 2021 10:12 AM

Where would you get to if you went in a straight line from any coastal point on earth? Now you can find out. Cartographer Andy Woodruff has created a simple web page that lets you click on a coastline and see where the straight line path from there ends up (Spoiler: It's quite often Australia).

Since the earth is very nearly spherical, lines that appear straight form curves when plotted on a 2D projection. So straight lines from the coast of Australia hit both coasts of the continental US. Going back from America, you can go straight to India, or from the west coast of Africa to Japan. And my favourite is the straight line from the Antarctic that goes up the Pacific, through the Bering Strait, across the Arctic sea and hits Europe from the north. That's a very great circle.

Have a play and see if you can guess where your straight line will end up.

posted by YoungStencil (13 comments total)

Very cool. I need a globe to spin in order to grasp some of those, like some lines from northern Japan or Russia all the way to Liberia.
posted by TreeRooster at 10:24 AM on November 30, 2021

Nice! Since I was a child this is something I always think about when I'm at the ocean looking out across the water to the far horizon.
posted by Atom Eyes at 10:32 AM on November 30, 2021 [2 favorites]

See also: The Longest Straight-Line Ocean Path Around the Earth

Total distance: 19,940 miles

Also fun to consider: what a compass needle does as you travel long 'straight line' distances like this.
posted by Insert Clever Name Here at 10:43 AM on November 30, 2021 [6 favorites]

Reminds me of the classic Missile Command videogame, but in a good way.

And, of course:

MetaFilter: It's quite often Australia
posted by chavenet at 10:47 AM on November 30, 2021 [3 favorites]

I'm sitting next to a globe and I think that something in this is off. In this app, much of the East Coast of the US goes to Australia but looking at a globe it seems to go south of Australia.
posted by bdc34 at 10:48 AM on November 30, 2021

From Boston I see... Perth.

Home. The literal other side of the world.
posted by Your Childhood Pet Rock at 10:54 AM on November 30, 2021 [3 favorites]

There is a point in Alaska from which you can "see" East Africa!
posted by ArgentCorvid at 11:41 AM on November 30, 2021

Technically a straight line will send you into space, or burrowed deep into the ocean...

(is slapped in the face with a fresh trout)

Okay, carry on.
posted by credulous at 1:25 PM on November 30, 2021 [1 favorite]

credulous: "Technically a straight line will send you into space, or burrowed deep into the ocean..."

Technically that depends on what kind of space it's embedded in.
posted by signal at 3:52 PM on November 30, 2021 [2 favorites]

Woodruff was one of the people behind Bostonography, a site that attempted to answer cartography questions of interest to Bostonians, such as the spot in Boston farthest from a Dunkin' Donuts.
posted by adamg at 7:22 PM on November 30, 2021

Seeing the great distances and strange curves traveling in supposedly straight lines over the ocean, George decided to change his course. He had set himself on the goal of leaving his sea-side home. He had not considered anything but ordinary, two-dimensional space. The surface of a sphere was bizarre, unnatural, and not for him. So, he abandoned his boat, turned around, and started walking. He resolved to walk in a straight line, as far as he could, to get away from, well, something. In fact, the original purpose of his journey had escaped him, and was replaced by his resolve to go straight from his location, in normal, ordinary, natural, two-dimensional space.

Though his mental fitness was of somewhat more concern than he realized, his physical fitness was not. He walked for several kilometers before stopping.

He looked down and gasped. Below him, about a meter down, was the ground.

How did that happen? How was he floating in the air? As a two-dimensional man in a three-dimensional world, he was confused. And like all two-dimension beings, after he looked down, he fell.


(The site is neat. It didn't work on mobile for me earlier but then worked fine on desktop.)
posted by sillyman at 8:16 PM on November 30, 2021 [2 favorites]

For those who get sea-sick: the longest straight overland path is "13,589 km long (8,443 miles), crosses 9 time zones and 18 countries and territories and connects the Atlantic with the Pacific Ocean. Liberia, Côte d’Ivoire, Burkina Faso, Ghana, (Burkina Faso), Niger, Chad, Libya, Egypt, Israel, The West Bank, Jordan, Iraq, Iran, Turkmenistan, Uzbekistan, Tajikistan, Afghanistan, (Tajikistan) and finally into China".
posted by BobTheScientist at 2:08 AM on December 1, 2021

I clicked "Start Fireworks" and now I think I'm high? Nice.
posted by Grither at 4:30 AM on December 1, 2021