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Contacting the USNO AA Department

Mailing Address:

Astronomical Applications Department
U.S. Naval Observatory
3450 Massachusetts Avenue NW
Washington, DC 20392-5420

Phone: 1 (202) 762-0001

DSN: (312) 762-0001

Fax: 1 (202) 762-1612

E-mail: Need help?

For best service, please contact us via the e-mail link above.