World Wind FAQ

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This is a list of frequently asked questions. If you have any questions please read this before asking in the Forums or Chat.


What is NASA World Wind anyway?

World Wind is open source Windows software that lets you zoom from satellite altitude into any place on Earth. Leveraging Landsat satellite imagery and Shuttle Radar Topography Mission data, World Wind lets you experience Earth terrain in visually rich 3D, just as if you were really there. See World Wind for more information.

Before Installing

Read System Requirements, Software Requirements, and Minimum configuration (just scroll down a page). World Wind is large and demanding of computer resources.

How can I download NASA World Wind?

The latest version is 1.3.2

This version is clearly marked if you go to Help->About in World Wind.

To get the latest version visit NASA_World_Wind_Download

What about the source code?

The source code is for developers. It is an additional download to the Full Install. If you just want to use World Wind and look around, all you need is the Full Install.

If you want the source code as well, download both. Once you run the full install, copy the Data directory from your World Wind full install directory into your source directory.

See Source Code for more information.

System Requirements

Windows 95,98,ME compatibility

Version 1.3 of World Wind shouldn't have a problem running unless it is due to an older computer / video card. I would appreciate some feedback on this. The latest version removed the texture converter code so the annoying black dos box shouldn't show up.

Software Requirements

The installer should detect and direct you to install these by default. If you are installing these because you believe there is an error, please install in the order listed below.

Microsoft .NET 1.1

Microsoft Directx 9.0c (December 2004 redistributable)

Minimum configuration

With the minimum configuration, performance and functionality may be less than expected.

Recommended configuration

  • 1.4 GHz or higher CPU
  • 256 MB of RAM
  • DSL/cable connection or faster
  • 3 GB of disk space


"Upgrading" to 1.3.2

There are several things to note when using the full install to upgrade to 1.3.2.


Older versions of World Wind used a configuration file named images.xml. Version 1.3.2 uses a file named @images.xml. You need to manually delete or rename C:\Program Files\NASA\World Wind 1.3\Config\Earth\images.xml or you will have duplicate options available on the toolbar.

Blue Marble

The Blue Marble imagery has been removed from the installer in order to reduce the size of the initial download. The imagery will now download as you use World Wind.

If you have an old version of World Wind you can move the images to the new folder and you will not need to download them again.

  • Old location: C:\Program Files\NASA\World Wind 1.3\Data\Earth\BlueMarbleTextures
  • New location: C:\Program Files\NASA\World Wind 1.3\Cache\Earth\Images\Blue Marble Tiled (1km per pixel)

CRC Error

Version 1.3
  • Some people recieve a CRC error when downloading the installer. This is caused by a corrupt download. Please redownload the program. (I would highly appreciate if someone could check MD5 sums as listed on the NASA World Wind Download page, and verify that this is a corrupt download. Also, if you repeatedly receive the same corrupt download from a particular server, please notify us immediately. User:Llynix)

Error writing file ______

  • The installer requires about 700 megs on your windows drive (usually c:) to install. This is regardless of where you install it to. Normally users who don't have room to decompress the files have this problem.
Version 1.2e and older versions

Please install the Latest Version.

Problems After a Successful Install

World Wind Fatal Error dialog box

If you get this error when World Wind loads try setting your display to either 16 or 32 bit color. There are reports that 24 bit color is causing this issue.

Every time I try to run the program it crashes with a "JIT debugger" error message.

Yikes, these are the worst. A few notes when trying to debug these. The process ID and thread ID are pointless and don't really help at all. Any other error codes you might receive may be helpful. Do not be concerned that there was no debugger found. As we get more organized and get more of an idea what errors are coming up I will try to post additional information here.

Some people have reported that installing the software requirements listed above has fixed their issues.

For knowledgable people this may help!

Error x135

More information is needed. I would like a full error code (If I recall this is a hex code, and it has a C in front of it followed by a lot of zeros.)


This error occurs when you try to run a .NET application but .NET is not installed (or is corrupt). To solve this error message, either install, or remove and reinstall .NET.

Error x02

More information is needed. Would appreciate the full error code.

cordbg.exe !a 0x5b4 code

More information is needed. Perhaps a .NET 1.1 issue?

<- Yes, it is. It is a Compatibility Problem. To fix it: Uninstall all with .net. Then delete in the Windows Directory and (maybe) in Programs (directory).

After that, reboot (!!). Then start the install of WW 1.3.2 with about 46 MB. WW will ask you to doenload .net. Click ok, and install. After that: REBOOT !! (if WW don't ask you to install, you forget something to delete..To fix, see up )

After rebooting, start the install again, then it want to install DirectX runtime. Say "ok". At the End, install WW. Finsihed.

Program Crashes with "unable to load font 'Tahoma Bold' (9em)?"

This is a known issue and should be fixed in 1.3.1

Please download the latest patch.

My video card isn't working

Check out the Video Card Compatibility list. Please, by all means, edit it depending on whether yours works.

Ensure that your video card drivers are up to date.

Try going to Start->Run and typing 'dxdiag'. This should load up the DirectX Diagnosis program. Under Display please make sure everything is working and enabled.

Why am I getting an error about "mscorwks.dll"?

This is an old error that shouldn't be affecting users anymore. I would like feedback if someone does experience it with 1.3 or higher.

Most likely, you've got .NET 1.0, but World Wind requires .NET 1.1. Just download it from here, and you should be up and running.

More Debugging Help

This blog post points to several verification tools to make sure .NET is installed OK [1]

My computer is crashing/hangs

Most likely you have a hardware/driver problem. Test your computer stability with 3D graphics by running for instance 3DMark or other DirectX benchmarking software.

Issues Downloading Tiles

To make sure there is no server-side problem check Server status page.

Download Monitor

World Wind version 1.3 has a download monitor which can be very helpful diagnosing problems. Hold down Control (Ctrl) and hit H.

Why am I getting 'Problem connecting to server. Trying again in 2 minutes'

Several possible reasons:

  1. May be the server is down. You could say... try again in 2 minutes.
  2. You may be behind a blocking proxy/firewall. You'll need to configure a port remapper, or hunt down an admin to help. See below.
  3. Make sure you have installed .NET Framework 1.1 SP1. (Issue WW-6)
  4. You could be in a country that blocks access to worldwind sites & download servers. Try to find a proxy? We haven't yet had any confirmed reports of this.
  5. Remember to use the HTTP Download Monitor (CTRL+H) to see what exactly is going on.

Is there a way to set a proxy?

Press Alt+Q to edit the proxy settings. The default setting is to use the Windows default proxy settings.

Proxy Issues

If using the proxy settings in World Wind doesn't work you may want to try using a portmapper such as AnalogX PortMapper.

Why are the wrong image tiles showing up?

Possibly and probably due to the server bandwidth issues.

A workaround is to delete the numbered folders in the "cache" directory, but then of course you have to re-download all the images the next time you run the program. It's not obvious which particular cache files correspond to the "bad" areas.

You can also use a DDS viewer to browse and delete the offending files:

  • Nvidia's DDS viewer — By installing this you can switch to thumbnail view in the explorer and find and delete those nasty tiles.
  • Another good DDS format reader is Irfanview.

Also it is entirely possible that you are viewing more than one layer. Go to the layer manager and under images make sure only one box is checked. Otherwise things look very messed up.

If you do manage to find a "bad" tile using a server and upon reconnecting keep on downloading that same "bad" tile, please kindly record the filename and level (folder number) of the tile and let someone know. I should probably point to a wiki link but I don't know where it is right now.

How are the tiles named?

The name depends on the image layer, all are named first the latitude and then longitude. Tools and Information could be found at Map Coordinates

Imagery related questions and tips

The questions we get every day

Aah! I zoom in and it's all blurry! Help!

If you're looking in the United States and it's blurry please read Why can't I see my house/car/etc?.

If you're looking outside the United States please read Can I use this for international locations?.

Why can't I see my house/car/etc?

USGS Imagery of Washington, D.C.
USGS Imagery of Washington, D.C.

AKA Why am I not getting pictures like this --->

That is the USGS Urban Area Imagery. USGS Urban is about .25m/pixel and only covers certain areas in the United States. These are the color images you may have seen. You can generally see cars with this layer. Note that it is only available for select cities, if you are not looking at the right place the images will be white. A list of available cities can be found at USGS Urban Areas.

Alternatively you can use the USGS 1m / topography which covers most of the United States, but is in black and white color. You can see most buildings and roads. You can probably find your house.

More information below.

Can I use this for international locations?

The United States Geological Survey (USGS) only has high resolution data available for the United States. However, the LandSat 7 data is available globally.

The LandSat 7 imagery has a lot less resolution than the USGS Ortho imagery. However, if you still don't believe the resolution is as good as it should be, click the sample images in LandSat 7 and compare your results. If the images are of different quality it may be a downloading issue - see Issues Downloading Tiles.

While there is high resolution imagery for many other locations, most of this imagery is licensed and is not freely available. If you know of any public domain or unrestricted datasets that we can incorporate please feel free to tell us about it.

The OneEarth add-on is an attempt make use of public wms servers for providing high resolution imagery. Several countries have data available.

We encourage all international users to contact their local politicians about releasing GIS data for all to use.

Pivot Irrigation
Pivot Irrigation

What are these crazy circles?

These are fields watered by a method called pivot irrigation. See this thread for more information.

When was this imagery photographed?

Depends on the layer. The NLT Landsat7 and OnEarth Landsat7 are from 1999 to 2003, with 2000 being the most active year. The USGS 1m Digital Ortho varies more. It was taken from 1990 to 2000. Search for a US location though TerraServer® and look for the USGS entry. The USGS Topo maps vary from within the past few years to more than a decade ago. Streets and building locations in particular may be quite out of date even if the terrain has changed little. USGS Urban Area Ortho dates from 2001 to 2004 and some areas are still being photographed, you can see the dataset ages at the USGS site.

Can I see the world in real-time?

This just isn't practical and won't be possible anytime soon. To do this requires a network of satellites dedicated to covering the earth. Just to provide as much detail as the base layers WorldWind loads first, the camera resolution on each one has to total about 100 megapixels. Perhaps the military has such a network, but it is certainly off-limits to anyone else. The images have to be received on the ground and processed. Then they all have to be combined where they overlap and corrected for the distortion caused by the earth's curvature. Finally after compressing the imagery from gigabytes down to several hundred megabytes, a server has to send it out to everyone. This requires an enormous amount of bandwidth for the server. Even if that weren't a problem, the internet connection for the majority of high-speed users is still too slow for more than about one update every hour.


With the new landsat, what's with the colors? Why isn't my area covered?

NLT Landsat 7 button
NLT Landsat 7 button

Nasa Learning Technologies has stated there will be additional tweaking and alterations to the coloring. There will be a white paper describing the techniques used, and it will improve over time.

Consider this NLT global mosaic version 0.1, you haven't seen anything yet.

NLT servers are working around the clock to process the entire world. Currently only certain areas are in place. Please be patient your area will be there very soon.

The NLT dataset is not yet as high quality as the original ("OnEarth" or "Community") Landsat7 datasets are. The NLT dataset has not been pansharpened yet. NASA feels it is of higher priority to complete a "rough copy" then it is to sharpen it as that takes 4x as long. As soon as coverage is complete look for a pansharpened layer to start trikling around the globe.

Problems connecting to OnEarth / Limited resolution compared to 1.2e

Recently OnEarth, who was serving the original Landsat layer, blocked access to World Wind users.

This is why older versions of World Wind do not work without the proxy/mirror patch, and why newer versions of World Wind (1.3) use the proxy patch by default.

Lucian at the onearth server has also asked us not to proxy the data. At this point the only access to the old landsat is the incomplete mirror served from

Work is underway to remedy this situation.

Latest news (2005-04-24): See for a patch that addresses this issue, and for the related announcement on the NASA site.


How do I load the .25 meter resolution maps, as shown in the screenshot of D.C. on this web site?

USGS Urban button
USGS Urban button

You can access these images by either selecting Layer Manager->Images->High Resolution Terrain Mapped->USGS Urban Area, or clicking the USGS Urban button.

All I see is white tiles when viewing the USGS Urban data!

USGS urban data is not available for all areas. If you aren't looking in the right place (in one of the cities listed at the Terraserver website, you'll see whitish green, and nothing else. The Urban Layer Highlighter is extremely helpful locating areas.

How to make use of the USGS layers

USGS is the acronym for U.S. Geological Survey. In other words, the data that is available in the USGS layers is only for the USA. While it is possible that similar data is available for other parts of the world, most of it is not freely available, and therefore is not incorporated into World Wind. See Using_the_USGS_Layers for step-by-step illustrated instructions.


Why does <insert mountain or other relief feature> not look like it should?


This is due to the fact that the elevation data, SRTM, is taken much like a bat's echolocation or sonar measurements - the elevation is "sounded" from a satellite. Unfortunately, these "soundings" are only taken about every 90 meters, so the data isn't incredibly accurate. As a result, mountains and such (for example, Matterhorn) may look strange. Imagine the satellite collects elevation points in a grid. So it flies over the Alps where two peaks are 50 meters apart. It takes one reading, say, 40 meters away from one peak's top, but manages to hit the highest point of a different peak right on the top. It never hits the first peak's tippy top.

Referring to the illustration, say the vertical blue lines are measurements taken. The red line will be what Worldwind shows, grey being the actual landscape. The left peak shows as being higher in WW, but the right one is actually the highest.

In addition, some surfaces look bumpy that shouldn't be, such as airplane runways. This is caused by different materials and ground coverings giving false readings becuase of the way they reflect the radar. For more on the method used to collect the data, see the JPL Website.

Google Earth

Which is better, Google Earth or World Wind?

Well, we like to think WorldWind is better. Give you two quick reasons why? Glad to- here you go: WorldWind is open-source (FREE), and more powerful in many ways than Google Earth. OK, so not everyone will agree, and frankly, that is quite alright with us.

The fact is, they both are sophisticated programs with amazing feature sets, and they both have features that the other would benefit from. But as similar as they are, and (perhaps more so) as they seem, Google Earth and WorldWind are not entirely comparable, due to significantly different focuses and development history/philosophies. Many of us use both programs, depending on what we wish to accomplish. In some aspects, each program has distinct advantages over the other, and so we will leave it to you to decide which you prefer (if you absolutely must have a favorite) - below are just a couple of examples.

It is easy to construct a set of criteria by which either one can be made to seem inferior, but the truth is that they are two very different products aimed at different audiences. Google Earth uses commercial satellite imagery, and thus has much more data (and more recent data) available to users than World Wind. On the other hand, Google Earth is lacking the Scientific Visualization Viewer capabilities of World Wind, and cannot be extended with user-authored add-ons. Moreover, World Wind provides direct access to the downloaded DDS and JPEG satellite images, and the open source nature of the program means that anyone can get the source code and 'roll their own' version of the program. Try doing THAT (or many other WW-specific features which make this software so great) with Google Earth!

For many people, the ease of using Google Earth and the abundant commercial imagery, along with easy personalization features, make it the preferable software. On the other hand, the images which GE downloads are locked in a data cache which cannot be accessed outside of the program. In addition, not only is Google earth NOT open-source, it in fact costs money. Certainly, the free version is good enough for many people, but it is extremely limited in terms of actually manipulating any data. OK, Plus and Enterprise versions give excellent value for the cost - but somehow that doesn't compare to Free price, or free data [ as in 'free of the cache' get it? :-) ]

Ok, bad jokes aside, WorldWind is totally free. It is also easy to use. There are no limits to what you can do with WorldWind, and it won't cost you a dime (except for all those missed days of work while you zoom in on your Favorite President's Ranch and try to figure out what he spends those long vacations doing). It includes a myriad of advanced functions and capabilities, and it will NEVER cost you anything. That is great- I LOVE free software. But there is another aspect to this that many people don't usually consider: while commercial software can pay the big bucks to get a bunch of programmers to rapidly incorporate a lot of functionality, and get a bunch of high resolution images that tax dollars aren't allocated for, there are some things money just can't buy. For those, and for many other things, there is Open-Source. What am I talking about? Glad you asked. I am talking about the long-term benefits of user-supported and developed software. If you would like an example, take a look at what Firefox has accomplished, and how it sets the standard for security, usability, and just plain coolness! (if you don't agree, you probably work for a corporation which is threatened by Firefox's success, or maybe you were just born a little 'challenged.') WorldWind benefits from diverse input from a user community which has the power to shape its development. This has led to a proliferation of 'add-ons' and 'plug-ins' which can be thought of as something like all those great extensions for Firefox. And this is only the beginning!

'Wait!', you protest, 'Google Earth has lots of stuff like that, too!' Yes, Google Earth has a whole lot of great user contributions, and this is one thing that makes Google Earth such an amazing program. And Google itself owes much of its success to its policies of allowing users access to certain API's, or allowing them to participate and play with things a lot- this has really helped to stimulate new applications and rapid development of various technologies. Google is to be commended for their foresight and tradition of 'doing things a little different.'

But there is a significant difference between allowing developers and users the ability to work with the program in pre-defined parameters, and what WorldWind allows, which is total access to everything! In this area, and in others, WorldWind will always win out over similar products that aren't free and open-source, no matter how many features they might have, and how high the quality of their imagery.

Google Earth Plus: a good deal. WorldWind: priceless.

(and don't take that comment about skipping work to zoom in on president's ranches literally - but if you do, and you get caught, PLEASE DON'T TELL ON ME!) :-)

Cache and data related questions

Can you make the amount of cache adjustable?

For World Wind version 1.3.2

  • Press ALT+ Q to bring up a dialog box where you can change this setting

For World Wind version 1.3.1.x

  • Please see your WorldWind.exe.config file. Open it with notepad (or any text editor) and you can easily adjust the cache size.

Can I copy my cache data to another computer?

Yes you can. Click here for discussion.

Can I use my 1.2e cache in 1.3?

Yes you can. See: Converting 1.2e Cache for use in 1.3

How large is the data set? Is it available for download?

Collectively the data sets are around 4.6 Terabytes. As such they are not available as a full package for localized download. There are, however, several data sets available for download as cache packs.

How about bittorrent for the data sets?

Because of the size of the data used, and the limited amount of data users download of the total available data, it is unlikely that p2p would make much of a dent in the problem of serving that data.

But see above.

Known Issues

Is there a way to narrow down a search for a place?

We realized this problem almost immediately (there are approximately 2 million places with 3 million more about to be imported) and we're going to associate a "Place" with a country or geographic identity. Perhaps you will type in "Paris France" and you will only get matches that have those two keywords. Also, if anyone hasn't noticed, the searching tool is case sensitive, and that will of course be changed as well.

In addition, we want to display more meta-data information about a particular place, such as the type of place(mountain, populated place, beach...), and perhaps attributes such as population or elevation. We of course are open to suggestions that anyone else might have in terms of what would be useful.

Several people are working on placenames right now. Stay tuned.

There are place names all over the place!

Yes, the amount of placenames is a bit of a nuisance, and we're working on ways to remedy this problem. We still want those placenames in there — we just don't want them to take up so much real estate on the screen.

Side note: if you go to the layer manager (viewlayer manager) under placenames, you can click off certain ones. It may be helpful to remove the one labeled "US Anthropogenic Features" which contains info about churches, schools and other landmarks in the US.

The entire time the application is running, it uses 50-100% of the CPU, why?

World Wind was not coded for performance, sadly. At least, you can rest assured that this problem is very common and most users experience it - there is nothing wrong with your computers. This will get optimized in future releases, but we're still heavily in the Research & Development stage.

Also there are a few bugs attributed to high CPU usage. Check out: [2]

Borders are in the wrong place, fix them!

The data to build the original borders was correct data for when it was gathered. Some areas have since become outdated. As basic as country borders might seem, it's actually been very hard finding good and updated data. If someone has a source for updated borders, it can be integrated into World Wind, but because of priorities there is much more to improve first. Since this is an open source project, users are encouraged to help fix borders and submit them.


How can I extract data from Worldwind for use in other modeling and mapping applications?

All the data is cached in the installation folder under the "Cache" directory. It's organized by the dataset, however, images are in DDS compressed format. Please see above for DDS viewers.

You may have more luck reading up about the WMS protocol, and then interfacing with the same servers that WW connects to.

Are images on World Wind copyrighted?

The Landsat Global Mosaic, Blue Marble, and the USGS raster maps and images are all Public Domain.

Can I use images on World Wind for commercial purposes?

The various servers you receive data from do request that you give them credit, however this is not required. You may do what you wish with these images.

What is the most proportionate "vertical exaggeration"?

Although it seems that 2 or 3 should be the "correct" vertical exaggeration, "1" is the correct and real vertical exaggeration. More correctly, "1" means that the vertical height is multiplied by 1.0, whereas vertical exaggeration of 3 means that vertical height is multiplied by 3.0.

Secret Keys

  • Wireframe: Ctrl+W
  • Diagnostic Info: Ctrl+D
  • HTTP Monitor: Ctrl+H


Future Versions

When will the next version be out?

Check the Road Map for information on future versions.

Do you think you could add boundaries of other sub-national entities, such as Swiss cantons, Australian states, and Canadian provinces and territories?

Chris : It's coming.

Llynix - the only reason these files aren't in there is they haven't been generated yet. If you have some free time, and a basic knowledge of computer programing why not volunteer to convert them?

Please see Additional Boundaries

Update - A ton of people took the call and made up boundaries, but now we need to sort them, get them in one place, and check the validity and political correctness of these files. Then integrate them into the WW boundary pack. Boundaries for the Canadian provinces and territories are now included.

Meanwhile boundaries could use some optimizing.

How about other planets?

We already have coverage of the Moon, and user-created coverage of Mars. Other planets may come in the future. :)

I would love to see a feature that showed day/night in realtime say taken from the USNO atomic clock. Perhaps a setting where you could follow the terminator and such.

It's on our list, slightly more elevated now that you asked for it.


Chris : We actually have plans to import a "Military-Grade" star map. It's probably overkill, but we like it that way.

I think Chris is referring to:

Maybe we could use same star catalog as Celestia:

You could also consider the star catalog from Stellarium:

Will there be an option to export animations/movies in the future?

Windows Media encoder allows screen capturing (all or selected area) and converts to .wmv video. This works very well but does require a substantial amount of video memory and CPU usage.

The encoder can be downloaded for free here


What license is World Wind released under?

Nasa Open Source license v1.3.

Will World Wind remain always free?

In short, yes. It's a government funded program and as such cannot be charged for (other than through federal taxes).


The program itself is open-source and will always be free. Access to NASA provided data will also remain free. However, there might be private companies that want to provide their data through World Wind (perhaps magazines or encyclopedias) and perhaps might charge a fee for access to their data. As long as there are people who want NASA provided data, and are using World Wind for that purpose, it gives the departments in charge of providing data a reason to ask for more funding to improve bandwidth to the data.

Why did you decide on C# and DirectX?

See this forum posting: [3]

Mac and linux ports?

Since this is open-source, we encourage any OSX programmers to start a port and we will try our best to provide whatever resources we can towards the effort. Right now our development staff consists of one programmer and one graphics designer, but we are an ambitious duo so we will do our very best to please everyone.

For more information:


In what areas do you need the most help? How can I contribute?

Check the How to Get Involved page to see how you can help with the World Wind project.


Copyright Questions When Using Images From World Wind


What data does World Wind use and where can I access it?

World Wind Data Sources

Where can I find more links?

Please see this forum : [5]

And this forum : [6]

Simplified Chinese Version of this FAQ

SC Unofficial FAQ

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