alt Hacker NewsNot NSA - you'd have someone from US Bureau of Industry and Security tracking you down (no pun) for most likely violating export controls if you were to openly share information on building the technology.
Celestial tracking is a dual use technology (See 7A004 or 7A104) - https://www.bis.doc.gov/index.php/documents/regulations-docs...
Openly publishing information in e.g. a book (or presumably a website) does not count as exporting. Releasing software is a bit more hazy, but has been defended[1].
[1]: https://en.wikipedia.org/wiki/Pretty_Good_Privacy#Criminal_i...