You are here: Home USNO Astronomical Applications Almanacs and Other Publications USNO Circular 181
The USNO websites,,,,, and are undergoing modernization efforts. The expected completion of the work and return of service is estimated as 30 April 2020. Please submit a requirements form to the USNOPAO if the information you are seeking is not accessible via other means.

USNO Circular 181

Nutation Series Evaluation in NOVAS 3.0 by George Kaplan

Circular_181.pdf — PDF document, 332 kB (340693 bytes)

USNO Master Clock Time
Javascript must be Enabled