TLE Tools Basic


Update 10 Nov 2014 - Version 0.91 includes advanced mode which adds additional features. Read the FAQ section for further information.


TLE data is the foundation of satellite tracking programs. To access the TLE data, tracking programs traditionally use third party organizations such as, and These third party organizations download and package the data from which is the web access point for data supplied by the US Military for use by others. The third party organizations provide a valuable service by organizing and packaging the TLE data sets into files. These files are ideal for people starting out in our hobby.

If you are open to considering a different method of accessing TLE data, continue reading. This is not some earth shattering stuff that will solve any problems with your station or help you work an additional ten thousand grids but it is possibly worthwhile and/or interesting.

These hard working third party organizations all do an excellent job and deserve more praise than they receive, they are not the issue. The issue lies lies in the fundamental nature of what they are trying to do. There are tens of thousands of objects in the Space Track data base. allows us all easy access to this database. The dilemma for all third party providers is which of these objects to include in their lists and how to organize the lists. There is a wide variety of interests in the amateur satellite community which makes creating generic lists even more difficult.

A good way to think of this is to consider a grocery store. There are many thousands of different items in the grocery store. If access to the grocery store worked the way our access to TLE data currently does we would not be able to go into the store and select the items we need. There would be a layer of third party providers who would go into the store for us and try to determine what items we might want and put them in carts in some logical way. Each cart would have a label on it that may or may not describe the contents of the cart. Our only option would be to buy a number of these pre loaded carts, take them home and then when we need something we would try and determine what cart it is in and find it.

There is a possible issue related to freshness of the items in our grocery cart. The third party providers fill their grocery carts from time to time on their own schedule so there are almost always fresher items available in the store. Another possible issue relates to new food items. When will these new food items show up in the third party providers carts.

If you are thinking this is not a good way to do things and why not just go into the grocery store with your own list and get the items you actually need directly from the store you are right on track.

The key is - do not try to anticipate what the user wants and then pre-package it but rather give the user a simple tool to create as many or as few lists as they want, with the lists organized and named the way they want and the satellites in those lists named the way they want.

'TLE Tools' is a Windows program for fully automated direct access to the TLE data without going through third party organizations. It allows you to organize, create and name lists of the satellites you actually want and give the satellites in your list the names you want. Current TLE data for the satellites in the list is then downloaded directly from After the TLE data is downloaded it is checked by generating actual orbit data. This will help filter out TLE data from satellites that have decayed or have other TLE data set issues. After the TLE data has been checked the lists will be automatically copied to other location(s) on your computer for use by your satellite tracking program(s). This entire process is automated and can be set to run each time you logon to your computer and/or at fixed time intervals.

Like many programs it will take a few minutes to set 'TLE Tools' up but this has to be done only once with only occasional minor changes from time to time as new satellites become available.

-- SpaceTrack Lists --

Refer to the 'Space Track Lists' screen shot shown below.

The first step in using 'TLE Tools' is creation of a 'Space Track List' which contains a satellite name and a NORAD number for each of our satellites. This list will be submitted to which will return a current TLE data set for each of the satellites in the list. will use only the NORAD numbers to retrieve the TLE data so you can use any satellite name you wish. The 'Space Track List' is shown in a data grid in the middle of the screen shot.

The data grid is a very powerful tool that is easy to use. There are two columns in the data grid we are using. The column labels are displayed at the top - 'Sat Name' and 'NORAD'. If you click on a column label it will sort the data grid by the contents of that column. Click on it again and it will sort in the reverse order. Click on a row to select it. When you have selected a row press the 'Delete' key to delete that row. Click on a column in a selected row and you may edit that column entry. Click on the blank row at the bottom of the grid to add a new row.

Create a new 'Space Track List' by entering a name for the list (.txt extension required) in the 'Space Track List Name' text box and click on the 'New Space Track List' button. You could enter all the data for you new list manually but there is an easier way. 'Web Lists' are third party lists available on the Web. 'TLE Tools' downloads lists you specify. Use the 'Web List' drop down box to select the web list you wish to use. The satellite name and NORAD number for each of the satellites in that list are shown in the 'Satellites in Web List' text box. Click on an entry in the 'Satellites in Web List' text box and it will be added to your 'Space Track List'. Your 'Space Track List' may contain satellites from one or more of the web lists. You may also add satellites manually for new satellites that are not yet in the web lists. You may delete satellites from your list by selecting the row in the 'Satellites in Space Track List' data grid and pressing the delete key. When your list is complete click on the green 'Save Space Track List' button. You may edit an existing 'Space Track List' by selecting it from the 'Space Track List' drop down box shown at the top middle of the screen shot. Remember to save the list if you make any changes. Click on the 'Delete Space Track List' button to delete the currently selected Space Track list.

To help you get started a 'Space Track List' is created for you. You can practice on this list or delete it.

You can have as many lists as you want. Dividing satellites into logical groups like Cubesats.txt, Ham.txt, Weather.txt and/or Beacons.txt is one approach. It is quite easy to change things later if you wish.

Some hints will be provided now and then that relate to SatPC32. 'TLE Tools' was not written solely for use with SatPC32. It is a general purpose program that should work with most all tracking programs that use NORAD format TLE data.

I have found that putting all the satellites I intend to use with SatPC32 in a single 'Space Track List' creatively named SatPC32.txt and then using this list as the only 'source file' when creating groups in SatPC32 works well for me. Since the list contains only the satellites I actually use it is not that long and is easy to use. The updating of this single 'source file' is handled automatically by 'TLE Tools'. Since we have set the satellite names to what we want in 'TLE Tools' there is no need for the SatPC32 AmsatNames.txt file. Since all the satellites are in a single 'source file' there is no need to cut and paste between various 'source files' with notepad to use TLE data sets from more than one source file in a group.
Another way to organize your 'Space Track Lists' is to create a list for each of your SatPC32 groups. If you use the name of your group for the name of your list it is easy to organize.


Refer to the 'Options' screen shot shown below. After the space track list(s) have been created the next step is to set the program options.

Passwords entered into the 'Options' screen are stored only in an encrypted form. To enter a password click on the password text box, delete the Xs and enter your new password. When you have entered the new password click on the green save button. This will encrypt and store your password and then replace the displayed password with 'XXXXXXXX'. Your passwords will never be displayed by 'TLE Tools'.

Space Track Update:
When this check box is checked all of your 'Space Track Lists' will be updated from the Space Track web site. For normal program operation this check box should be checked. The values in the 'Space Track User Name' and 'Space Track Password' text boxes will be used to access the Space Track site. If you do not have an account on the site it is very easy to get one and it does not cost anything. Go to the web site to set up an account.

File Copy:
The Space Track Updated files may be automatically copied to up to 4 different locations on your computer. This is handy for copying the files directly into the folder used by your tracking program for TLE data.


SatPC32 normally stores its 'Source Files' in a directory in your user area. On most systems the path will be something like this 'C:\Users\ yourUserName\AppData\Roaming\SatPC32\Kepler'. If you want to use your list(s) with SatPC32 it is necessary to copy them into this directory. 'Tle Tools' can do this automatically. My user name is 'Thomas'. If you look at the options screen shot you can see the path to my SatPC32 source file directory in the text box in the 'File Copy' area in the middle of the screen. When the 'File Copy' check box is checked our updated files from will be copied to the directory. If SatPC32 is installed on your computer in the default location and 'Path 1' is empty it will be set to your SatPC32 Kepler directory. Nothing will be copied unless the 'File Copy' check box is checked.
If your 'Source File' lists in SatPC32 do not look sorted it is due to interaction with the SatPC32 AmsatNames.txt file which adds another level of satellite renaming to the mix. You can easily fix this by clicking on the SatPC32 'Satellites' menu item => 'Sat Names' => 'Use Sat Names from Source File' radio button.

Be sure to click on the green save button after updating the options.

The image below shows the main screen for 'TLE Tools. You can run this program from the Windows start menu. Clicking on the 'OPTIONS' menu item will bring up the 'Options' screen described above. Clicking on the 'SPACETRACK LISTS' menu item will bring up the 'Space Track Lists' screen described previously. Clicking on the 'TASK SCHEDULER' menu item will bring up the 'Task Scheduler' screen. Clicking on the green 'Run' button will cause the program to run. The program will cause

- your 'Space Track Lists' to be submitted to
- the TLE data sets that returns will have their names adjusted as you specified on the 'Space Track Lists' screen
- all the data sets will be checked by calculating actual orbit parameters for two days after the current day
- Any defective TLE data sets will be deleted
- the list will be sorted by satellite name in ascending order
- the updated files will be copied to the folder you specified on the options screen
- a copy of the files will be places in the c:\ProgramData\TleTools\SatData\TleLists folder

When it runs you will see a console window open for a short while. Depending on things like how many lists you are updating, how many satellites are in the lists, the speed of your computer, the options you have selected, the speed of your internet connection ... it will take more or less time to run. When it is finished the console window will close. The results of the run are displayed in the text box in the middle of the screen.

-- Web Lists --

The 'Web Lists' screen shown below is used to select what if any existing third party lists you wish to use as sources in the 'Space Track Lists' screen described above. Most users will not need to change anything on this screen. The web sources are displayed in a data grid. You may edit the list using the same method as described in the 'Space Track Lists' section of this page. The 'File Name' can be whatever you wish but should end in .txt. The only difference with this data grid is the 'Use' column. This column determines if the list is downloaded or not. If you wish to change the setting click on the row then click on the 'Use' column for that row. You will see a drop down box that offers 'YES' or 'NO' choices. Pick the one you want. Remember to click on the green 'Save' button when you are through. You can bring up this screen from the 'Web Lists' menu item on the 'Space Track Lists' screen.


The 'Task Scheduler' screen shown below is used to allow 'TLE Tools' to run completely independently without any user interaction. When the 'Run At Logon' check box is checked the TleTools console program will run once each time you logon to the computer. Your TLE data sets will be updated directly from, checked for TLE errors and copied into your satellite tracking program directory as set in the 'Options' screen each time you log on to your computer.

If the 'Run On Schedule - Every x Hour(s)' check box is set the console program will run every x hours. For the example shown in the screen shot it will run every three hours.

If both check boxes are checked it will run when you logon and every x hours.

If neither check box is checked the scheduled task will be deleted from the 'Windows Task Scheduler' list of tasks when you click on the green 'Schedule Task' button.

The path to the TleToolsConsole.exe program should be shown in the 'File Path To TleToolsConsole.exe' text box by default and should not require changing. Click on the green 'Schedule Task' button when you are finished. When the 'Schedule Task' button is clicked the old task definition is deleted and replaced with the new one.

NOTE: The 'Task Scheduler' is not available if you are using XP.

If you find this program useful consider a donation to

-- FAQ -- 

Q: What files need to be edited with notepad.
A: None. I discourage you from editing any of the 'TLE Tools' files with notepad.

Q: Does the TLE check always work.
A: We do not live in a perfect world. 'TLE Tools' calculates orbit parameters at a day in the future. If an exception is thrown during the calculations the TLE data is deleted. This will catch most errors due to orbit decay or other problems. The only potential issue with this is the fact that different satellite tracking programs use different code for calculating the orbit parameters. A TLE data set that tests OK with in 'TLE Tools' may throw errors in a program that uses different code for orbit calculations. The reverse situation is also possible.

Q: What about program updates.
A: 'TLE Tools' automatically checks for updates and will let you know if one is available.

Q: Does it work on a Mac.
A: It works fine on my MacBookPro running Windows 7 and 8 under Parallels.

Q: Can I distribute the lists I create to others.
A: Read the Space Track user agreement.

Q: How do I enable the advanced mode.
A: In the 'File' menu on the main 'TLE Tools' screen there is a clickable 'Advanced' option. The documentation for only the advanced functions is available here.
TLE Tools Advanced Functions

Click on the link to download the file. After you unzip the file click on the TleTools Setup.exe file to install the program. During the install you will be offered the opportunity to install the program in a different location - I do not recommend it unless you have a good reason to do so. The program will show up in the Windows start menu and can be uninstalled from the Control Panel like any other Windows application. It is early days for this program so please let me know how it goes - thanks.

<Windows 8>
If Windows 8 chokes when you run the setup program click on 'More Info' and then 'Run Anyway'.
</Windows 8>

Good Luck and Have Fun - 73 de W9KE