Exploring

Choose a topic below. (click to view)

Guided tours drive WorldWide Telescope to show visuals to present a topic or tell a story. Tours show data as a series of slides with transitions between view points and visualizations.

You can browse a library of tours by clicking “Guided Tours” tab. You can also save and share tours yourself.

If you are browsing from within WorldWide Telescope, you will see a list of categories, such as “Learning WWT” and “Planets”.

Within each category is a list of Tours; as you mouse over each you will see a description and can download it by clicking the Play button.

Some tours take a few seconds to download. When it is finished downloading, the tour title will show up right of the uppermost menu. If you interrupt the tour to explore you can return to the tour by clicking the title.

Pushing Play after the tour is downloaded starts the tour. Tours play full screen. If the mouse is over the menus they will keep on top of the tour, so move it to the display to hide all menus.

You can hit F11 to go back and forth between a windowed and full screen view of WWT.

Menus will be displayed when you are in the windowed mode or you hover your mouse over the menu location.

When tours are running and the menu is shown you can pause them by clicking the Pause button on the left.

When the tour is running you can skip to a slide by clicking on the desired slide.

Tours can have separate narration and music tracks. You can adjust the volume of each separately.

You can save the tour so you have a local copy you can edit and share.

We will talk more about authoring tours in another tutorial, but you can start making content by first making edits to existing tutorials. Once you have saved a local copy you can update that saved version by clicking the Save button.

WorldWide Telescope allows you to explore real images obtained from some of the world’s most advanced telescopes. These are the same images that professional astronomers use in their research.

When you are in Explore mode, you can investigate the current view in more detail. You can zoom in and out using the Page-Up and Page-Down keys on your keyboard or the scroll wheel on your mouse. You can move your view by clicking and moving your mouse in the main window. You can also rotate the view by holding down the control key while you move your mouse.

In the left-hand part of the lower menu, there is a pull-down to select what you are looking at and what imagery is displayed. You can look at the Sky, which is what you are looking at now.

look at sky

You can also select an exact image of the Sky with the Imagery pull-down. Currently, you are looking at the optical view of the Sky, as captured by the Digitized Sky Survey. You can use the Imagery pull-down to see the Sky in other wavelengths, such as this infrared view of the sky from the IRAS satellite.

look at wavelengths

You can also look at Earth, which brings up a 3D view of our planet as seen from space. Note that this view only shows the Earth and does not include the effect of lighting from the Sun. Just a blue marble in an empty universe.

look at earth

You can look at Planets, and other solar system worlds, such as Mars. These views also show just the body of interest by itself.

look at mars

In the next viewing mode, you can look at various Panoramas, which are wrap-around images taken from the surface of Earth, Mars, and Earth’s Moon.

look at moon

The last viewing mode allows you to explore a 3d model of the Solar System, and indeed the entire universe, at least as much of it where we have good models. The major components included are the Solar System, which includes planets, dwarf planets, moons and asteroids. Beyond the Solar System is the Hippoarcos catalog of stars. Then further out is a model of the Milky Way including a face on artistic view of our galaxy. Pulling further out galaxies from the Sloan Digital Sky Survey (SDSS) are shown.

look at solar system

In addition to looking at the sky in various ways, WorldWide Telescope can view planets from orbit or the surface. In order to do this we have to select Look At to either “SolarSystem” or “Planet”. Looking at the Planet isolates the planet and does not show the sky as a background. Your motion is also only relative to the center of the selected planet.

You can also Look At SolarSystem. This allows you to investigate all the bodies of our solar system. For this example we will explore Earth as it has the largest amount of information. First, we have to enable the display of the most detailed datasets. This is done in the Layer Manager controls on the left side of the screen or selected Show Layer Manager under the View menu. Under 3d Solar System, make sure “Mulit-Res Solar System Bodies” is checked.

Now under the Earth object you can adjust what datasets you see. To see the most realistic clouds, select “8k Cloud Textures.”

In order to see some additional data you will have to be looking at the Earth rather than SolarSystem. Let’s select that now.

One interesting thing you can do is view a cutaway of the Earth that shows the interior layers of structure. You can select this view in the Layer Manager on the left.

Let’s put the Earth back to together and look at how we can view the surface.

By default Earth views show 3d terrain and aerial data from Bing Maps. Note, that when looking at the Earth there is not a sky behind to view so atmospheric effects will be different than when viewing Earth in the Look At SolarSystem mode.

Explore Earth and the Planets in WorldWide Telescope to experience the Solar System yourself!

Astronomical Images, defined as those with overlay sky coordinates can be loaded directly into WorldWide Telescope (WWT) in several ways.

Loading Local AVM-tagged Images

Astronomical Visual Metadata (AVM) is a way to storing information about the original astronomical image in the header of a standard image file, such as TIFF and JPEG. This standard uses existing header infrastructure and populates it with astronomy-specific metadata. The relevant metadata to WWT is:

  • Image Name
  • URL
  • Credits
  • Caption
  • World Coordinate System (WCS) coordinate information

The idea behind AVM is to allow visualizers to manipulate colors, add annotations etc. and maintain the description of that manipulation – e.g., original data location, color representation – so that subsequent people know how it was created and how to interpret it. For WWT, coordinates allow the image to be placed at the correct location on the sky.

You can download AVM-tagged data from a variety of data sources. If your favorite source of image data provider doesn’t currently include AVM tags, you can direct them to the AVM resources below. If you want to get a test image, you can browse for one in the Astropix website, which aggregates AVM-tagged images - http://astropix.ipac.caltech.edu/link/5c. Once you have it, you can add the data to WWT by:

  1. Make sure you are in Sky Mode.
  2. Under the Explore Tab, click on Open/Astronomical Image…
  3. Browse to the appropriate file.
  4. WWT will load the data into WWT and add it to a default collection called “Open Collections,” shown in the upper left-hand part of WWT. You can right click and add it to a collection of your choice for image organization after you have loaded it.
  5. You can right-click on the image in the collection and select “Properties” to see the image, coordinates, image name, caption, URL. These values are all pulled from the AVM tags when the file is read.
  6. You can adjust the cross-fader to change the opacity of this overlaid image on top of the current background.
  7. You can also adjust the Image Alignment by pressing CTRL+E to open the Image Alignment instructions.

image alignment instructions

Loading FITS Files
  1. Make sure you are in Sky Mode.
  2. Under the Explore Tab, click on Open/Astronomical Image…
  3. Browse to the appropriate FITS data file. This can be pulled from the Internet or from an attached telescope or a local file.
  4. WWT will load the FITS file into WWT and add it to a default collection called “Open Collections,” shown in the upper left-hand part of WWT. You can right click and add it to a collection of your choice for image organization after you have loaded it.
  5. Note that FITS files contain pixels, which are mapped to physical coordinates, and data values. To view the image data values must be mapped to colors. The default color map is a linear greyscale one where the lowest value is mapped to black and the highest to white, with linear steps in between. You can interactively adjust this mapping by clicking on the Scale button, which opens the Histogram dialog box.
  6. In the Histogram dialog you can select the mapping function between Linear, Log, Power, Square Root and Histogram Equalization.
  7. You can change the minimum and maximum data ranges by moving the red and green vertical lines, respectively. If you move the green line to the left of the red line, this inverts the mapping and low values will be show white and high values black.
  8. Grabbing the blue circle in the middle will allow you to keep the mapping function width of the function and move it through the histogram left and right.
  9. You can adjust the cross-fader to change the opacity of this overlaid image on top of the current background.

adjust the cross fader

AVM Resources:

WWT can read Web Mapping Service (WMS) data from various data services. WMS data are served by various sources, and often show time-varying map overlays which can be displayed on the Earth or planets. In the example below, we will add a time-sequence of WMS maps showing wild fires in Yellowstone, but a similar process would be used to add other mapping data for other planets.

mapping data
  1. In the Layer Manager, under the Sun, right-click on the Earth and select "New WMS Layer" to bring up the WMS wizard.
  2. In this example, we will use the default server at NASA Goddard Space Flight Center, which is identified by the Web Mapping Service URL field “http://svs.gsfc.nasa.gov/cgi-bin/wms.” You could also enter a URL from the list below or construct your own list to choose from. Set the “Server Name” to something like “Goddard” and click the "Add Server" button to add this to your Server List.
  3. Click on “Goddard (http://svs.gsfc.nasa.gov/cgi-bin/wms), and then click the “Get Layers Button” receive a list of available layers.
  4. Data providers categorize WMS data; for this example, expand – by pressing the “+” to the left of “Agriculture,” and then further expand the “Wildlife Growth around Yellowstone National Park in 1988” to show “Wildlife Growth around Yellowstone National Park in 1988 (1024x1024 Animation).”
  5. yellowstone wildlife growth
  6. Then press the “Add” button in the lower right. Close the dialog box by clicking “Close” to the right of “Add” button. Now in the Layer Manager under Sun/Earth, there is a layer entitled “Wildlife Growth around Yellowstone National Park in 1988 (1024x1024 Animation).”
  7. Since these data represent a time sequence as you scrub through time in the SolarSystem mode, the lighting and Earth rotation will change as well and you will not view the same location on the Earth as time changes. To be able to scrub through time, you should Look At: Earth.
  8. Make sure the checkbox next to “Wildlife Growth around Yellowstone National Park in 1988 (1024x1024 Animation)” under Sun/Earth in the Layer Manager is checked.
  9. Find Yellowstone National Park on the Earth.
  10. Move the Time Scrubber, which is shown below the Layer Manager. You will see a sequence of different maps. Note, the colors are chosen by the WMS data provider and you should go to the data source to find out what the color represent. Note, that as you move the Time Scrubber, Observing Time in the View tab also shows the detailed time/date.

Here are some WMS sources to experiment with:

  1. NASA GSFC – http://svs.gsfc.nasa.gov/cgi-bin/wms
  2. MBARI – http://odss.mbari.org/thredds/wms/ucsc/sst
  3. GIBS – http://map1.vis.earthdata.nasa.gov/twms-geo/twms.cgi
  4. NEOWMS NASA SCI – http://neowms.sci.gsfc.nasa.gov/wms/wms
  5. JPL NewMoon – http://onmoon.jpl.nasa.gov/wms.cgi
  6. NASA OnMoon – http://onmoon.lmmp.nasa.gov/wms.cgi
  7. NASA On Mars – http://OnMars.jpl.nasa.gov/wms.cgi
  8. NASA WorldWind - http://data.worldwind.arc.nasa.gov/wms
  9. Moon Modeling – http://onmoon.lmmp.nasa.gov/sites_a/wms.cgi
  10. Moon Modeling 1 – http://onmoon.lmmp.nasa.gov/sites/wms.cgi
  11. NASA OnEarth WMS – http://onearth.jpl.nasa.gov/wms.cgi
  12. NASA Earth Observatory – http://neowms.sci.gsfc.nasa.gov/wms/wms

(from http://www.layerscape.org/Home/VisualizingContentinWWT)

Virtual Observatory (VO) Tables are a standard exchange format of catalog data and queries to registries. VO Tables allow you to find, plot and interact with a wide variety of catalogs that have VO table interfaces.

First orient the view to a location, for this example the Pleiades open cluster.

  1. Make sure you Look At is set to Sky.
  2. Under the Search Tab, select SIMBAD Search…
  3. Enter Pleiades in the search box. This will orient your view to the Pleiades cluster and zoom in.
    screen shot of simbad search dialog
  4. Under the Search tab, open the VO Cone Search/Registry Lookup…
  5. In the field NVO Registry Title Like, enter Pleiades, then click NVO Registry Search button.

Screen shot of NVO Registry Search Button

This will populate the bottom of the table with a list of registries (registered catalogs in this case).

  1. Click any row to search that catalog. This will load values into Base URL. For this example, select ZYJHK photometry in Pleiades… Since you are looking at the location of the Pleiades, you can click the checkbox next to from View. Set the Verbosity drop-down to Medium in order to return photometric measurements at all observed bands, rather than the default positions if the default Low is used. Then click Search on the right.

screen shot of medium verbosity from view

This will plot the catalog entries of the returned table on the background sky image. The default is to plot circles at each location. Also, this table is added as a layer (default name is VO Table) under Sky in the Layer Manager on the left.

  1. If you close this table, you can always right-click the VO Table in the Layer Manager and select VO Table Viewer.