Debris Assessment Software
The NASA Debris Assessment Software (DAS) utility provides assessments that can verify compliance of a spacecraft, upper stage, and/or payload with NASA's requirements for limiting debris generation, spacecraft vulnerability, postmission lifetime, and entry safety. Successful verification of a design in DAS demonstrates compliance with NASA debris mitigation requirements. Historically, DAS analysis has proven acceptable in meeting compliance requirements of many other agencies in the U.S. and around the world. It does not address the inherent design reliability facets of NASA requirements, but addresses all Earth-related orbital debris requirements that make up the bulk of the requirements in the NASA Technical Standard 8719.14C.
NASA will periodically update DAS to reflect the latest understanding of the man-made debris environment in Earth orbit. Users are encouraged to check this page regularly for news and updates. The DAS team may be reached through the contacts listed on this page.
Updated 04/04/2023, the current version of DAS is 3.2.4, optimized for Microsoft Windows 10. DAS 3.2.4 provides upgrades for the user-defined material model in the reentry modules, a new project file upgrader for improved backwards compatibility, and a new binary file format for solar flux tables. As in the previous version, the probability of small-object penetration due to meteoroids must be assessed outside DAS at this time. Please contact the NASA Meteoroid Environment Office (William Cooke) and Hypervelocity Impact Technology teams for guidance on meteoroid assessments.
Although approved for public release, NASA regulations require that a Software Usage Agreement must be obtained to acquire a copy of the NASA-developed software, DAS. To begin the process, please press the "Request Software" button in the Software Catalog. Included in the installer and also available for separate download are the DAS User's Guide and Software Release Notes. Due to file size limits, the installer has been split into several .zip archive files: the main installer and five separate files containing debris environment data. Users must download the main installer (which includes the debris environment for years 2016-2030) and additional environment files required to assess mission years beyond 2030.
Click here to download the latest DAS Solar Flux table • Updated 12/21/2023
- Request DAS and complete the Software User Agreement.
- Download and run the DAS 3.2.4 Software Installer (includes debris environment through 2030).
- Download additional debris environment files required for years beyond 2030. Uncompress these archives and move the population files to your installed “DAS3.2.4\data\” folder.
- Whenever a new solar flux file is released (quarterly), download the DAS Solar Flux table from this page. The file date is in the file name. Place the file in the DAS installed data\ folder, renaming it “solarflux.bin” to replace the existing file.
- DAS relies on the Microsoft Visual C++ Redistributable runtime libraries. If not already installed, the user should install/update both the “x86” and “x64” versions provided by Microsoft.
- NOTE: Users' existing project files from DAS versions 3.1.x and earlier may not be compatible with DAS 3.2.x due to changes in the postmission disposal requirements and the exclusion of assessment of intentional explosions. In these cases, users will need to transcribe inputs into the new DAS version. DAS 3.2.4 will automatically reformat earlier project files, rendering them incompatible with earlier versions of DAS.