USNO Data Services STILL offline

George Reynolds

I get and download my annual sunrise/sunset, moonrise/moonset, and twilight times calendars from the U. S. Naval Observatory's  Data Services division of the Astronomical Applications Department, but they have been OFFLINE since October 2019!  They said their "modernization" would take until 30 April 2020.  Then later, they said it would be up in Fall 2020.  NOW they say they MAY be back by Spring, 2021!  Here is their notice:

This US Naval Observatory Website is undergoing modernization and will be offline starting Thursday, 24 October 2019.   The expected completion of work and return of service is estimated to be spring, 2021, subject to change due to potential impacts of COVID-19.  Please visit and submit a Requirements Form to the USNO PAO if the information you are seeking is not accessible via another means.

Fortunately, the Sun's rise and set times do not differ more than a minute or two from one year to the next, so I can use the 2020 calendars in 2021.  The same goes for the timing of civil twilight, nautical twilight, and astronomical twilight; however, the Moon's rise and set times are totally different from year to year, so I need to get that data another way.  Fortunately, there are other sources, but the easiest one was to go to the USNO site.


George Reynolds

"Solar System Ambassador" for South Hampton Roads, Virginia
Back Bay Amateur Astronomers (BBAA)


Join to automatically receive all group messages.