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speedfreak227
10-27-2005, 05:45 AM
i can see that the images aren't properly meeting at their edges but shouldn't they at least be white instead of blue? :confused:

sounds like a conspiracy to me. :x

http://www.v-j-enterprises.com/holearth.html

speedfreak227

Stadsman
10-27-2005, 06:25 AM
LOL, very funny. What people think of these days :lol:

araT
10-27-2005, 06:43 AM
Its not funny! its fact! :stare: The mole people live below the crust of the earth - they like scratching peoples eyes out to get to the gooey grey brain behind :whoa:

:lol: :lol:

T.

speedfreak227
10-27-2005, 07:04 AM
ok, i don't honestly believe there's a hollow earth but i AM wondering why it shows as water rather than ice.

aren't you?

speedfreak227

araT
10-27-2005, 08:31 AM
Well aren't you the party pooper :p

I have no idea why its like that, I guess the only way we will trully know is to go hassle the devs at the official forum (http://bbs.keyhole.com) :)

T.

Lemenant
10-30-2005, 11:31 AM
this is also a question that i had myself. If somebody have a answer, even if it is already answered in another forum, thanks to put it here again for me.

GEH4EVR
11-02-2005, 11:30 AM
I think there must be something going on because the south pole has ice so why dosent the north pole, :confused:

Highlander739
11-04-2005, 08:06 PM
No ice? Simple..... The satellites used there must only register land masses, so the ice at the North Pole would not show up since it is on water. Look at Greenland/Alaska/etc and you see plenty of ice. The South Pole is on a land mass, so the ice shows. Over the sea area, it only shows the sea bed through the water.

That's also the reason why you can see terrain in the middle of the oceans, and not water, unless it is a hi-res photo of a certain area. Zoom in to around 2500km above Iceland and slowly scroll south. Then you can follow the Mid-Atlantic Ridge, which is where the tectonic plates are pulling apart, all the way down to the Antarctic continental shelf.

araT
11-05-2005, 02:54 AM
Wow!! very nice spotting Highlander! thats amazing :D

T.

speedfreak227
11-05-2005, 06:28 AM
i noticed the mid atlantic ridge a long time ago and it's really cool to see, but i don't understand something...... if the satelites show the floor of the ocean in some places, why not in all? there are obvious ocean waves near islands and just off the coasts.

is the satelite image seeing through the ice? wouldn't ice register just as solid as earth?

i don't understand satelite imaging technology so if someone can explain this better i'd really appreciate it.

speedfreak227

Highlander739
11-05-2005, 08:26 AM
i noticed the mid atlantic ridge a long time ago and it's really cool to see, but i don't understand something...... if the satelites show the floor of the ocean in some places, why not in all? there are obvious ocean waves near islands and just off the coasts.

is the satelite image seeing through the ice? wouldn't ice register just as solid as earth?

i don't understand satelite imaging technology so if someone can explain this better i'd really appreciate it.

speedfreak227


Well, I ain't an expert either (just a humble electrician), but I would say you see more at the coastlines as the crust of the earth rises to form the land masses you would see more as there is far less water above the sea floor. Also, some areas will have a higher resolution than the centre of the Pacific, for example.

As far as "seeing through the ice" at the North Pole, I would guess that would be because ice is far less dense than land so the ice wouldn't register on sats that only pick up "solid" objects. As they slowly add more images, I'm sure we'll see some photos of the ice caps and hopefully some 'bergs floating around too.

I guess you have played with the National Geographic bits in Africa, but if not then have a look at the Megaflyover stuff. Some great waves on the African coast there

arbitrary
11-05-2005, 09:08 AM
Correct me if I'm wrong, but as far as I know, it's not possible to determine water depth accurately from a satellite. I think what Google Earth displays in the oceans is not satellite imagery, but a representation of sonar data obtained from ships or submarines. This would also explain the lack of ice on the north pole. If it was really a satellite image, oceans would look like the high res pictures of water in lakes or coastal areas. Just compare to any "real" picture from orbit, you certainly can't see the continental shelves, ridges, and stuff like that.

speedfreak227
11-05-2005, 09:22 AM
that seems like a reasonable explaination.

but i still like my hollow earth cover up theory as a close second.

speedfreak227

SSSALVI
10-26-2006, 11:57 AM
Just see Arctic and Antarctic regions in MS Encarta World Atlas.

The snow cover at North pole is very less as compared to South pole and the solid ice is very near to polar regions only.

Coming to oceans .. GE is using only the bathymetric data for oceans and not the satellite imagery. That is why they are so 'bland'. Even the Microwave ( Radar ) imaging can't penetrate water for large depths.

Explaination by arbitrary is correct.

Shashi

Professormp3
06-10-2007, 03:51 AM
Hey zoom in to the north pole looking straight down about 3150 miles high. Stop the zoom there and then move the picture gently around the screen by holding the left mouse button. You will see theres an artifical patch covering the pole starting from the 80 degree latitude line. Check out the attached file. Its the same thing at the south pole.

Captain Hornblower
06-10-2007, 10:22 AM
Try to wrap a piece of paper around an orange. Maybe you can figure out the problem Google has at the poles ;)

sladys
06-10-2007, 12:13 PM
If you look at this site about map projections you can learn more why it's a problem about the poles:

http://members.shaw.ca/quadibloc/maps/mapint.htm :)

Wyzig
07-17-2007, 05:31 PM
Ask Gore! Global Warming is the answer, It's all gone.

Hungry Donner
08-13-2007, 05:13 AM
Actually there is a relatively simple solution to this problem: construct the Earth as a geodesic sphere and use dymaxion projection for the map file.

Or without the jargon: construct the sphere out of lots of triangles, think Spaceship Earth at Epcot. In fact when you strip out the bezier curves and other fancy stuff this is exactly how you construct a sphere as a basic 3D model.

Now each triangle gets its own overhead slice of the map. There are no poles with such a model or map projection so whether you're looking at the Congo or Antarctica things would be stretched out or displayed any differently.

To be honest it's a shame GE doesn't use a system like this. It might make some things a bit more complicated but it would allow for a far more even display of the maps. It would also allow you more freedom in how to use image overlays, even if the actual mechanics would be a bit trickier. For example, putting an image overlay near the poles does all sorts of wacky stuff to it - but this wouldn't be an issue with my suggested set up.


So I suppose now I need to learn how to program so I can create this amazing piece of software and learn about the programming pitfalls it would stumble into :)

SSSALVI
08-16-2007, 06:04 AM
Try to wrap a piece of paper around an orange. Maybe you can figure out the problem Google has at the poles ;)

Captain ahs given a very apt analogy of the problem.

This was extensively discussed in this link.
Google Earth Hacks Forums > Google Earth > Great things you've found >
really really weird?

Quoting from that link :




The point in the placemark is exact North Pole where all the Longitudes merge into a single point.

The terrain at north pole is sea.

For the sea area GE uses only numeric data indicating the depth of sea at a particular place ( bathymetric data, not imagery acquired by camera. ) . This data is coarse resolution data and therefore has very poor resolution and each pixel may span about a kilometer by kilometer at equator.

E.g. You can see this by zooming in the sea water ( till the scale legend at bottom left shows about 50 kms )near 1332'42"S 1521'29"W .... there are squares of varying intensities of blue and black. They are the actual pixels.

Now imagine what will happen if you try to bring closer the northern corners of a pixel .. it will become a triangle.

That is what happens at the poles.. the pixels become triangular ( spherical triangular actually ) and so each pixel at the pole is triangular and the vertex of each triangular pixel is at pole, giving rise to the flower like appearance for the area around pole and each 'triangle' represents the color corresponding to average color shade in that area

From your bookmark if you go up in altitude slowly then you start seeing next line of pixels surrounding the first set and then next ... and so on to ultimately the limit where the pixels become very small and you get a smooth picture of sea bottom.



Hungry Donner is right provided geometric accuracy is what you are looking for. But then the 'feel' of a spherical earth will not be there for most users who are laymen and use it only as a visual display and not for geodesy applications.

==========
S^3

Jolanta Zofia Nowak
08-16-2007, 07:49 PM
Try to wrap a piece of paper around an orange. Maybe you can figure out the problem Google has at the poles ;)

Sounds about right!

Hungry Donner
08-17-2007, 09:29 PM
Hungry Donner is right provided geometric accuracy is what you are looking for. But then the 'feel' of a spherical earth will not be there for most users who are laymen and use it only as a visual display and not for geodesy applications.
A Dymaxion projection map is odd looking, but that's only because it's flat. Looking at the orange example, Google Earth is taking a rectangular Mercator projection map and trying to wrap it around a sphere, which results in problems at the poles. However if you tried doing this with a DP map you'd get a perfect sphere! (http://en.wikipedia.org/wiki/Image:Dymaxion_2003_animation_small1.gif)

So the feel of a spherical Earth would be better perserved if GE used a DP map instead of the standard Mercator.

From the user's perspective there really aren't any drawbacks to this. So why didn't Keyhole do this? Most likely because the Mercator route is simpler, especially with the data set they were using. However it's worth pointing out that the DP route I suggest is actually how 3D objects are normally skinned by a computer. This is why the skin of a human figure (http://home.wnm.net/~bgriff/skin01.html) looks all weird.

Roman_Centurian1979
12-01-2009, 09:20 PM
Is it my imagination, or does it look like the earth is expanding? If you study the faultlines, it kinda looks like a balloon filling with air.

Forkboy2
12-01-2009, 09:44 PM
Is it my imagination, or does it look like the earth is expanding? If you study the faultlines, it kinda looks like a balloon filling with air.

I'm sure there is an expert on plate tectonics out there somewhere that will correct me if I'm wrong. But I think it is expanding in some places and pushing up to create mountains in others. Then you have the effects of weathering that wash the material from the mountains into the oceans and the cycle starts over. In the end, it probably all works out.