Satellite Ground Track Tool
This program and the corresponding tools will enable the customer to view the locations of various satellites orbiting around the Earth. This tool has the ability to zoom-in to a specific area to view possible satellite coverage from the present time or a time in the future.
Satellites included are: QuickBird-2, WorldView-1, Ikonos-2, GeoEye-1 and SPOT5.
Ground locations include are: Boulder, Colorado (Spatial Energy HQ); Houston, Texas.
Disclaimer: This tool can be used to view the area on the Earth a satellite covers on a given day. Due to naturally occurring variations of the satellite orbit, there is no guarantee that the satellite will actually have access to the area.
3 easy steps
Step 1: Go to AGI website and download (free) AGI Viewer:
Step 2: Download vdf file: STK_TrackSats.zip
From Spatial Energy website
Step 3: Open AGI Viewer and open STK_TrackSats.vdf file.
You’re now ready to start viewing the satellite locations around the globe. You should see a view similar to that in Figure 1.
Figure 1: Main View of AGI View with Satellites
COMMENTS ABOUT THE VDF FILE
The program is set up to have a run-time of 90 days. Once the run period expires, customer will need to revisit Spatial Energy website for an updated file.
The vdf file will be updated monthly. The monthly updates will account for the slight modifications in the satellite orbits which occur over time.
COMMENTS ABOUT THE VIEW of AGI Viewer
The program is set up to show night and day. One side will be lighter, while the other is darker. This represents night/day; however, note it does not take into account seasonal sun elevation in the extreme northern/southern latitudes.
Recall that imaging satellites only image on the descending pass (north to south); not ascending (south to north).
Most satellites show two sensor “cones”. The smaller cone is set to 15deg off-nadir. The larger cone is set to 30deg off-nadir.
GETTING STARTED and TIPS
START REAL-TIME SIMULATION
At the top of the AGI Viewer (under the toolbars), there are purple arrow keys. Click on the one that looks like Play. This will start a real-time simulation. The simulation should automatically start at the current date/time (in GMT).
MOVE TO FUTURE TIME
When the program is started, the time defaults to the present real-time (in GMT.) There are two ways you can move forward/backward in time. This is a useful tool to determine if a satellite will have access to a specific area on a given date.
Option 1: At top of viewer, next to the box with the current time, there is a slider-bar. You can move that forward to a new time. You have to play with it to get it to an exact time. NOTE: You can only move forward to a date within the vdf file “run time”.
Option 2: (Assumes user has a mouse with a scroll-button in between the two right/left mouse buttons). Hold down the right button on the mouse, at the same time, use the scroll button to move to a time in the future (scrolling up/forward) or a time in the past (scrolling down/backward.)
If you put your mouse on the earth and hold down the left button and move it around, the world should move around in 3-D. In this view, you can see the sensor “cones” in good detail (when zoomed-in). These cones are essentially the location on the ground which the sensor has access to on that pass.
Under the toolbar section, click on the magnifying option with a “+”. Like this:
Then go to the location on the world where you want to zoom in, and draw a box. It will zoom in so you can see things closely.
Option 2: Zoom-in or zoom-out by holding down the right mouse button, and move the mouse forward and back.
Example: On this date shown below, QuickBird has an access over Boulder, Colorado but not over Houston, TX.
BACK TO HOME VIEW
This button will always get you back to the main view of the whole world.
ADDITIONAL QUESTIONS OR ISSUES