User:TomServo/Walkthrough Text

Welcome to World Wind 1.3.1

This tour of NASA World Wind will show you how to use the program and introduce you to some of its features.

Let's start by turning on the Position Information display.

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Click this icon to display longitude, latitude, and other position information.

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This display tells you where you are as you travel around the globe.

The Layer Manager lets you choose what kinds of data, or "layers," to view. Click this icon to activate it.

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Let's open the High Resolution Imagery list and see what's available to use.

Important Note: You can add in other sources of imagery. Check the World Wind Central website and the World Wind Forum for "add-ons" to access the data.

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The default image layer selected is NLT Landsat. This is satellite imagery of the entire Earth at a resolution of 30 meters per pixel.

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To show the satellite imagery, let's zoom into the northwestern United States.

Landsat imagery (there are three Landsat sources) is the only imagery that covers the entire globe.

The other image sources included by default in World Wind cover only the United States. This is because high-resolution imagery of locations outside the United States are costly and difficult to obtain. World Wind accesses public domain data only.

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Notice this blue box? It means World Wind has downloaded an image and is processing it for display.

Red boxes on your screen mean World Wind is downloading imagery for that area.

There are several ways to zoom in:

Use the scroll wheel on your mouse.

Or, click and hold BOTH mouse buttons. Push your mouse forward to zoom in or pull back to zoom out.

Or, use the Home key on your keyboard to zoom in, and End to zoom out.

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As we hover over the northwestern United States, we zoom into Mount Saint Helens.

With Landsat imagery, we can fly down to 10,000 meters above sea level and get clear pictures. If we try zooming closer, no new imagery will downloaded, and the view will get blurry.

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This is about the "best" you will see with Landsat. An altitude of 11,000 to 14,000 meters is the prime viewing height.

But even with the limited resolution, you can see a lot of details clearly. Notice the lava dome forming in the volcano?

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Press and hold the right mouse button. Then drag the mouse toward you. You will see the volcano in 3D!

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Still pressing the right mouse button, move your mouse to the right or left to rotate your 3D view of the mountain.

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Let's look at Mount Saint Helens using one of the other Landsat views.

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This view uses OnEarth Landsat 7 Visible imagery. This is the same imagery as NLT Landsat, just processed differently.

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This view is pseudo-colored Landsat 7 imagery.

Now, let's look at the area using USGS 1-meter imagery.

This red download box, as you'll remember, shows what area is being downloaded.

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USGS Digital Ortho is 1 meter-per-pixel photography taken from an airplane flying a grid pattern over the area. Most Digital Ortho photos were taken in the middle to late 1990s.

With Digital Ortho you can zoom to an altitude of about 1000 meters, closer than you can with Landsat.

Let's zoom into the lava dome.

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You're looking at Mount Saint Helens' lava dome from inside the volcano!

You can also view the area as a topographical map. Let's look.

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Top-down view of Mount Saint Helens.

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Turn on placenames to find places faster.

Click here to show placenames.

You can view this area as a 3D Topo as well!

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With placenames turned on, cities, countries, lakes, and mountains are now labeled. As you zoom in, placenames get more detailed and numerous.

Now let's look at some really detailed imagery: "USGS Urban Area Ortho." USGS Urban covers major United States cities and is generally .3 meters per pixel in resolution.

Let's look at San Diego, California.

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The USGS Urban Area imagery is starting to load.

This imagery doesn't completely cover the United States -- it only covers select urban areas.

Patches of white mean that imagery doesn't exist for those locations.

We'll zoom in closer and look at the Golden Gate Bridge and Alcatraz Island near San Francisco.

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In this closer view, you can see San Francisco's Golden Gate Bridge and Alcatraz Island. Let's see Alcatraz in even greater detail.

The Golden Gate Bridge

Alcatraz Island

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Here we are 490 meters above the island. But we can get even closer.

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You can see people!

Here we are at 242 meters above the island. This is as detailed as we can get for this area.

In some areas, you can see clearly down to 100 meters in altitude.

Now, let's try using the place finder.

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To find a place in World Wind, use the Place Finder. It scans a global database of locations and displays results in the search window. Also, if you have coordinates, you can type them in and go directly there.

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Let's search for the White House in Washington, D.C.

Click the location you want to visit. Then click "Go" to zoom into the location.

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Here you can see what we searched for, the White House. Because of security concerns, the roofs of the buildings are obscured in this imagery.

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Now that we've covered some of the imagery layers, let's talk about some of World Wind's other features, such as MODIS.

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Rapid Fire MODIS is a "near real-time" image server. Usually a few days behind the current day, it downloads imagery from two satellites, Terra and Aqua, that orbit the Earth.

MODIS images cover various natural events around the world. The highest resolution is 250 meters per pixel.

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For example, let's look at a 500m-resolution image of a phytoplankton bloom in France.

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The image of the phytoplankton, recorded by one of the MODIS satellites.

World Wind also has a Web Mapping Server browser.

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The WMS browser is a way to bring external imagery and animations into World Wind.

This WMS server provides many images and animations that you can view.

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This image of vegetation in the western United States is from the NASA SVS server.

NASA SVS Icon

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Scientific Visualization Studio, or SVS, is similar to WMS, and contains both still images and animations.

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World Wind comes with a collection of add-ons. This icon activates Flags of the World.

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This add-on shows the flags for every nation on Earth. Move your mouse over a flag to show the name of the country.

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Now, let's look at the Landmark Catalog.

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This add-on shows famous landmarks, monuments, and natural wonders around the world.

The last add-on we'll look at is the Lewis and Clark Trail.

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You can follow the journey of Meriwether Lewis and William Clark in 1803 as they explored the western United States.

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World Wind provides some diagnostic tools. To solve connection problems or see what data is being downloaded, press Ctrl+H to reveal a download progress window. This shows you all of World Wind's data transfers.

Double-click on a transfer to get more detail.

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Thank you for viewing this introductory tour of World Wind!