STSORBIT PLUS Revision History ------------------------------ Each released version of STSPLUS uses a four digit revision code such as 9848. The first two digits indicate the year and the second two digits indicate the week of the year. In some cases, an additional letter suffix is added to distinguish changes occurring within the same week or to identify special versions. A partial week at the beginning or end of the year is counted as a full week. Using this method, a year will typically have 53 weeks although it is possible to have 54 weeks in a leap year (1972 is an example). The current year-week revision code is shown on the Julian Date display, Display Mode 7, in my program ASTROCLK. This file records the revision history of program STSPLUS through all of the minor twists and turns that usually accompany the evolution of such a complex program. It illustrates the tortuous process of maintaining and refining a program as ideas and problems are reported from every quarter. These notes may also be helpful to users who are upgrading from one version to another to find out what has changed. David H. Ransom, Jr. e-mail: rans7500@spacelink.nasa.gov Home Page: http://www.dransom.com http://tie.jpl.nasa.gov/dransom/ cp 5 Version 9848 -- November 1998 ----------------------------- -This is a MAINTENANCE UPDATE to add features for ISS and to correct a minor bug in the NORAD date. -Added internal 15x15 and 21x21 satellite icons for ISS, the International Space Station. The icons depict the linked Zarya (FGB) and Unity modules as will be the case following the STS-88 mission in December of 1998. The internal icons may be overridden by providing a satellite icon file with the name "#25544.ICN". -Added default satellite choice "ISS" if the TLE filename begins with "ISS". The TLEs with common name "ISS" will be selected from the file. -Corrected the NORAD date (example: "98325.990313") which showed the incorrect day of the year at certain times if the UTC Offset was positive, as in Australia, in which case the day of the year was one day low. Thanks to Peter Bennett for reporting the error. -Program documentation is essentially unchanged from Version 9838. Version 9838 -- September 1998 ------------------------------ -This is a MAINTENANCE UPDATE to implement GPS capability (via my program GPSSYNC) and to correct several minor bugs and other upgrades/changes. -A word of explanation: Thanks to my emergency major surgery for an aneurism in April followed by software work for NASA this summer, my usual update for STSPLUS has been delayed by some months ... -I have added the capability to link directly to my new program GPSSYNC, Version 9838 or later, to obtain current GPS time and position. Use ALT-F2 from the Main Menu to switch to program GPSSYNC. If GPSSYNC.EXE is not present in the STSPLUS directory, no action will occur. At this time, GPSSYNC has only been tested with GARMIN and DELORME GPS receivers. Other receivers may or may not operate properly. Program GPSSYNC is available separately from my Home Page or on disk via mail. Comments invited! -File WIN95.TXT provides an improved procedure for setting up STSPLUS under Windows 95/98. This procedure is RECOMMENDED for all Windows users! Thanks to Nicolas Biacona for the procedure! -Repaired a bug in the TLE file selection process (F2 from the Main Menu) that caused STSPLUS to lock up the computer if there were no files with filetype .TXT or .TLE in the current TLE directory. The program now returns to the Main Menu when this occurs. Press F7+F1 from the Main Menu to set the TLE path correctly OR place the .TXT/.TLE files in the specified directory. Thanks to Trevor Smith for the bug report! -Updated the displayed TLE filename if the Primary Satellite is among those updated with F2+& (auto-update). -With the advent of faster and faster processors, the Motion Map could be drawn twice in a single second. I've added code to cause the program to wait until the next second before updating the Motion Map. There is no effect with slower processors. -File STSLNDG.TRK has been updated to correct the locations of Miramar NAS and the Shuttle Landing Facility at KSC. Thanks to Stuart Edwards for pointing out the errors! -The small alphabet used for map labels has been upgraded to include accented characters (without the accents) for non-English users. -Corrected the circle of visibility color around the station location(s) when night vision is enabled (ALT-R). -Increased the length of Line 0 (common name) for the TLEs in file STSPLUS.INI from 15 to 20 characters to accommodate longer satellite names. However, the name length in the orthographic projection is still restricted to 19 characters by the screen layout so the 20th character may be truncated in that projection. -Updated file GPS-PRN.SCF with the current operational GPS satellites as of 15 September 1998. (The non-operational GPS satellites are not included.) -The dial-up GSFC/OIG RBBS was shut down effective 01 July 1998 and I have deleted all references to it. GSFC/OIG data and information are now only available via the Internet. As of 04 September 1998, the GSFC/OIG website address is: http://oig1.gsfc.nasa.gov/scripts/foxweb.dll/app01? -Various minor corrections and updates to this text. Version 9748 -- December 1997 ----------------------------- -This is a MAINTENANCE UPDATE to correct a problem with ALT-F1 from the Main Menu introduced in Version 9745. -Corrected a problem with ALT-F1 when more than 32 secondary satellites were present. The program halted with an error if more than 32 were present. Count-specific code was replaced by code which will accept any number of secondary satellites. -The text example display for ALT-F1 has been updated to reflect a slightly different format for the increased number of secondary satellites. -Updated several Internet addresses and the GSFC/OIG RBBS telephone number. -Added several entries to the Bibliography including Spacetrack Report #3. -Added my home page address at JPL. The content of my two home pages is identical and all FTP files are now at JPL. Users who wish to make direct FTP transfers may use the following address: ftp://tie.jpl.nasa.gov/pub/dransom/ Various subdirectories are present which include my software, current TLE data, and current/recent space shuttle missions. -Except for the relatively minor changes and additions above, the text is otherwise unchanged from the prior release. -A corrected version of IRIDIUM.SCF is also included. One satellite had the wrong NORAD Number. Version 9747 -- November 1997 ----------------------------- -This is a MAINTENANCE UPDATE to correct a problem with secondary satellites introduced in Version 9745. -Edits for one source module for Version 9745 were omitted in the final release of that version and caused display problems when using F6 from the Main Menu. The problem has been corrected. My apologies ... -I have included file IRIDIUM.SCF which contains data for the 39 Iridium satellites in active orbits as of 20 November 1997. When viewing the Iridium constellation, select any Iridium satellite as the Primary Satellite to accurately view your local circle of visibility. Iridium satelites in the lower orbits (Mean Motion = 14.3 or so) will yield the most accurate circle of visibility since they have the smallest surface area of visibility. I selected Iridium 8 for file IRIDIUM.SCF but the difference between the various Iridium satellites are relatively minor. -Note that secondary satellites #1 and #2 must still be set up for TDRS satellites although their display may be disabled with F10+F3+F2 set to SATS. STSPLUS requires that secondary satellite positions #1 and #2 be set for geosynchronous satellites or improper operation may result. -Use F6+F3 to load file IRIDIUM.SCF after first saving your present SCF file using F6+F2! Version 9745 -- November 1997 ----------------------------- -This is a MAINTENANCE UPDATE to increase the number of secondary satellites and to correct a minor bug. -In an effort to "keep ahead" of the Motorola Iridium constellation, the number of secondary satellites has been increased to 48. As of this release, there are 34 Iridium satellites in orbit. Because of memory limitations, this will have to do for the moment ... -Corrected the code to adjust the DOS clock if the Daylight Flag is changed using F8+F10. Versions since 9650 froze the program when this was done. The cause was a typographical error on a function declaration type. Thanks to John Gresham for reporting the bug! Version 9736 -- September 1997 ------------------------------ -This is a MAINTENANCE UPDATE, improving resolution on the manual map mode and correcting one minor problem. -The resolution of the manual map mode ("L"+"/" while orthographic map is displayed) has been increased by a factor of two. Use of the arrow keys now moves the crosshair one half of the current grid spacing. The map center latitude and longitude are now displayed to the nearest 0.01 degrees instead of 0.1 degrees. -Manual map mode now recognizes the primary and secondary locations. -When entering map coordinates in manual map mode, the default latitude and longitude are now the current location, primary or secondary. Press ENTER to accept the default values shown. -Corrected a constant typing problem (mixed type integer overflow within an expression) which caused automatic PCX file generation to fail if the numbered file exceeded 327.