unforum

[danteIL]

Okay it seems to me that most of these dots eventually appear in pairs if you refresh often enough. Back here I posted screencaps of two red dots. Below, I am posting a screencap showing two distinct green dots in Newfoundland-area. Is there another location other than Stephenville??

[mr.judkins]

I wondered that myself, dante, and tried a variety of other location names in the area - but to no avail... It's hard to konw - I've seen THREE dots appear close together in the China area, but we've only found one Pending location (Dongying), and two dots appear in the Denmark area (location not yet found)...

It seems strange to have navigation points so close to each other at multiple places...

[Ranger D]

Another email.

[ariock]

Got it:

[xnbomb]

Very nicely done! If at first you don't succeed, just assume an ancient/high-tech navigation system might miss by a fair amount, and make some guesses in general vicinity (especially ones that are contextually relevant based on the storyline).

I do enjoy thinking about these kinds of problems, so I wanted to stick a few images in here that show the difference between Great Circles and loxodromes. The following images show both starting at Stephenville, NL: The Great Circle (shown in white) has an initial bearing of 84 degrees. The rhumb line (shown in rum/purple) has a constant bearing of 84 degrees. Both are the prescribed length (20478 stadia or 3786382.2 meters).

First, here are both on a Mercator projection map (like Google Maps):



See how the loxodrome appears straight here, while the Great Circle is curved?

Next, here are both on an azimuthal equidistant projection centred on Stephenville, Newfoundland (Note: An azimuthal projection is the only 2-dimensional portrayal of a Great Circle line that will look straight, in particular when it emanates from the center of the projection ... the nature of the projection is that it shows true direction from its center):



Finally, here's a pseudo globe view:



Now, they both look curved.

As you can see, the rhumb line/loxodrome is in the ballpark, but doesn't quite make it to Wales by my calculations (the Great Circle at the same initial bearing is not even close ... an elegant illustration of how over ~4000km there is a big difference between the two). I used the WGS84 representation of the Earth, it's conceivable that the Omphalos mappers used one that is much less accurate. I'm not surprised though, in the sense that unless you have some more significant digits in the bearing, it is awfully hard to hit any target accurately from a great distance. I do wonder about getting the number of stadia quite wrong, though. Whatever their approximation of the Earth is, it's certainly not as good as the tools we have available to us.

[sixsidedsquare]

So, a bit of a summary,
(note: I used stadia as 184.9 m, and distances are likely to vary a bit depending on where you get them from)

-Traveling in the shortest path 'as the crow flies' from Stephenville to Cardiff:
--approx 3,889 km (21,033 stadia), at an initial bearing of just over 64 degrees

-Traveling on a loxodrome from Stephenville to Cardiff:
--approx 3,978 km (21,515 stadia), at a constant bearing of 85.3 degrees

I've been trying to make those fit to 3,786 km (20,478 stadia) at 84 degrees from Stephenville to no avail.

[Lysithea]

I know that Eli Hunt's podcast defined stadia as 184.9m, but the distance between Stephenville and Cardiff on google earth (about 3890km) would suggest a value closer to 190m was used.

190m is the approximate value given by wikipedia:

[Troag Lee]

[Mirkomick]

I yesterday focused on the german baltic coastal side, from Lübeck to Stralsund and had no hits (actually sorry for not mentioning that I guessed the red dot actually appeared to be in norhtern germany to me ) I will later try some cities form Lübeck northway to Flensburg, it really looks like it is somewhere in that area but then again, it might be anywhere in a 500km radius there, and that is a huge place to cover

[mr.judkins]

I agree on Northern Germany, the more I look at that dot I more I'm sure I originally assumed it too high up the map... and I too am running out of steam typing names into that command line - I've been working through the region between Hamburg and Hannover....

[AUZ505]

[chippy]

playing with the levels, it appears there are a few more green dots:


and click here to see the image for the whole area:

[Taurec]

[[M]]

[Mirkomick]