Does this place have a name?

[Neimo]

Edited because I did a poor job of explaining.

At 42.00S and 0.00E/W to the lower left there is a blur on the Blue Marble Tiled layer. There is nothing to see in the high resolution imagery. There is another, smaller dot at -39.72, -6.05. Does anyone know if these dots exist and have names? I've found a map of the islands surrounding Antarctica, and those two spots aren't on it.

**Kinda interesting**
To the left of both places is Gough Island, an uninhabited nature preserve that is part of Tristan da Cunha, 320km north-west and the remotest inhabited island on earth. To the south of the first mystery spot is Bouvet Island, a volcanic lump covered by ice and usually clouds. Last year's Alien vs. Predator movie was set there, though I haven't seen it. I highly recommend checking it out with the Landsat 7 (Pseudo color). Yeah I know ice turns radioactive blue like this, but with the cloud cover it looks even more neat and reminds me of a glowing stone.
**End kinda interesting**


I can point out for comparison that Isla Sala y Gomez (-26.46, -105.51) also shows up on the main map, but has no high res imagerery. It's a few hundred km from Easter Island. While we're over there, has anyone seen the 1111km wide strip of something to the south in the ocean that reminds me of a starfield? Anyone know why?

[Beansprout]

Which places don't show up in WorldWind - and which hi-res imagery set?

The NLT Landsat7 dataset *should* have everything on it now.

[Neimo]

At Lat. -42.00, Lon. 0.00, on the non-high res image of the world, there is a cluster of dim dots that indicate land. But all the Landsat7 tiles are black, for all three Landsat7 tilesets. If you look at the larger, brighter islands a few hundred km away, they have tiles. They also have real names and websites on wikipedia and maps.

[crcorp]

Originally posted by Neimo@Mar 31 2005, 06:55 PM
At Lat. -42.00, Lon. 0.00, on the non-high res image of the world, there is a cluster of dim dots that indicate land. But all the Landsat7 tiles are black, for all three Landsat7 tilesets. If you look at the larger, brighter islands a few hundred km away, they have tiles. They also have real names and websites on wikipedia and maps.

Quoted post

Am I right that you're referring to this spot: worldwind://goto/world=Earth&lat=-41.99985&lon=0.00000&alt=147740 ? These should be the islands Tristan da Cuhna and Gough... but I don't see any tiles of them in NLT, the LANDSAT show black tiles only...
I think that no imagery is available for this spot...
You see the same thing for the Azores (worldwind://goto/world=Earth&lat=38.71075&lon=-28.04279&alt=641166) some islands are missing in the LANDSAT data (although NLT has them).

[Neimo]

Originally posted by crcorp@Mar 31 2005, 10:10 AM
Am I right that you're referring to this spot: worldwind://goto/world=Earth&lat=-41.99985&lon=0.00000&alt=147740 ? These should be the islands Tristan da Cuhna and Gough... but I don't see any tiles of them in NLT, the LANDSAT show black tiles only...
I think that no imagery is available for this spot...
You see the same thing for the Azores (worldwind://goto/world=Earth&lat=38.71075&lon=-28.04279&alt=641166) some islands are missing in the LANDSAT data (although NLT has them).

Quoted post

Okay, I'm really sorry I tried to play Tour Guide. It distracted and confused my question. worldwind://goto/world=Earth&lat=-41.99985&lon=0.00000&alt=147740 is the mystery location that I'm trying to identify. This place: worldwind://goto/world=Earth&lat=-37.10719&lon=-12.28561&alt=40604 is Tristan da Cunha. Sorry I didn't use direct links before. I had noticed before that WW has copy and paste location options, but hadn't used them until now and forgot they existed. Gough island is here: worldwind://goto/world=Earth&lat=-40.32529&lon=-9.95845&alt=430360

I'm asking about the mystery location because it doesn't show up or have a name on any non-WW map I've seen.

[crcorp]

Originally posted by Neimo@Mar 31 2005, 07:36 PM
Okay, I'm really sorry I tried to play Tour Guide.ﾃつ* It distracted and confused my question.ﾃつ* worldwind://goto/world=Earth&lat=-41.99985&lon=0.00000&alt=147740 is the mystery location that I'm trying to identify.ﾃつ* This place:ﾃつ* worldwind://goto/world=Earth&lat=-37.10719&lon=-12.28561&alt=40604 is Tristan da Cunha.ﾃつ* Sorry I didn't use direct links before.ﾃつ* I had noticed before that WW has copy and paste location options, but hadn't used them until now and forgot they existed.ﾃつ* Gough island is here: worldwind://goto/world=Earth&lat=-40.32529&lon=-9.95845&alt=430360

I'm asking about the mystery location because it doesn't show up or have a name on any non-WW map I've seen.

Quoted post

For the direct links, don't worry direct links make it easier to let other people simply know where you're looking at, fortunately you discovered this nice feature B).
For the mistery location and the two (groups of) islands I mentioned, you're right...
I must admit I didn't check the coordinates, although I was looking at the same location as you were looking at... I checked the location in my atlasses and my world map, but I don't find any land on that spot...
Though MS Encarta World Atlas does show some interesting information on this loccation. It looks like a shallow part in the middle of the Atlantic. When MS drew them right, they're not islands, but just shallow waters compared to the rest of the Atlantic. Here is a screenshot of the place:

Hope this helps

[Neimo]

Thanks! It did help quite a lot. Seeing Microsoft reminded me that expedia.com (owned by MS) has rough underwater depth information. It turns out the two places I was trying to identify are indeed both underwater, but they do have names. The first one is called Discovery Tablemount. The other is R.S.A. Seamount, named for the Republic of South African (sic). Does anyone know what the two circles mean around R.S.A. seamount? The underwater edges of volcano craters perhaps? Or that the edges may even break the water's surface in the right tides?

I find it interesting that they show up so lightly on the WW low-res map. But I forget that the ocean has been digitally altered to be uniformly blue except where there are features to show. Perhaps those two are especially near the surface compared to other underwater features? Heck, maybe even when Blue Marble was being created whoever was working on that area thought they were above the waterline and so didn't paint over them?

Say, does anyone know if underwater terrain is just a matter of time and priorities? Or is the data not available for free?

[crcorp]

You're welcome
I didn't know that all ocean-data was erased from the Blue Marble... in that case I think they forgot something

For this underwater data, I wouldn't know why NASA would have to keep that information secret...

[Neimo]

Originally posted by crcorp@Mar 31 2005, 02:29 PM
You're welcome
I didn't know that all ocean-data was erased from the Blue Marble... in that case I think they forgot something

For this underwater data, I wouldn't know why NASA would have to keep that information secret...

Quoted post

Well I don't have any special information on how Blue Marble was created, but there had to be significant image processing. For one thing, the sea ice and icebergs were erased from the poles. Removing cloud cover could be done many ways, perhaps by photographing the same area twice, when the clouds had shifted. When clouds and ice are removed, there's still differences in sunlight intensity and what angle it's hitting the ground at. To me the oceans just seem too uniformly blue, like exactly the same color, to not have been significantly smoothed and color corrected.