Skip to main content (Press Enter).
Official Website of the United States Navy
About Us
Mission & Vision
Strategic Plan
History
Leadership
Commander
All Leadership
Organization
Naval Oceanographic Office
Fleet Numerical Meteorology & Oceanography Center
United States Naval Observatory
News from the Naval Observatory
Earth Orientation Department
USNO Earth Orientation Products
Daily Solutions
Weekly Solutions
Bulletin A
Contents of Bulletin A
Long-term Delta-T
USNO GPS Products
GPS User Information
Rapids
Ultras
UTGPS
USNO VLBI-based Products
VLBI Correlator Data
VLBI-based Earth Orientation Parameters (EOP)
Earth Orientation Information Center
General Information about Earth Orientation
Frequently Asked Questions About Earth Orientation
Suggested Reading
What Is Earth Orientation?
What Is Polar Motion?
What does the Earth rotation coordinate measure?
What is the Celestial Pole Offset?
What is a Leap Second?
How do we measure Earth Orientation?
What causes variations in the Earth's orientation?
Who uses Earth orientation information?
Publications About Earth Orientation Products
Scientific Publications
Earth Orientation Software
Precise Time Department
The USNO Master Clock
The USNO Master Clock
Time Dissemination at the USNO
USNO Alternate Master Clock (AMC)
Cesium Atomic Clocks
Hydrogen Masers at the USNO
Rubidium Fountain Clocks
USNO Time Scales
International Time Scales and the BIPM
Definitions of Systems of Time
Global Positioning System
Global Positioning System Overview
USNO GPS Data Categories Explanation
CGGTTS Data Format
USNO GPS Time Transfer
Leap Seconds
GPS Information: SA, DGPS, Leap Seconds, etc.
GPS Week Number Rollover
GPS Timing Data and Information
USNO Format Explanation
USNO Computer Display Clocks
Two-Way Satellite Time Transfer (TWSTT)
Telephone Time
Network Time Protocol (NTP)
US Eastern Time Zone NTP Servers
US Mountain Time Zone Servers
DoD Customer Servers
Astronomical Applications Department
Celestial Reference Frame Department
Optical/IR Products
Naval Oceanography Operations Command
Fleet Weather Center - Norfolk
Fleet Weather Center - San Diego
Joint Typhoon Warning Center
Exercises
ANTX
ANTX 2020
ANTX 2019
Press Room
News Stories
Press Releases
Photo Gallery
Video Gallery
Public Use of Limitations
Contact Us
Navy.mil Underway
Facebook
Twitter
Blog Feed
YouTube
Flickr
Pinterest
Instagram
United States of America Department of the Navy Seal
The Sky This Week
U.S. Naval Observatory's Weekly Blog
Results:
Tag:
Arcturus
Latest Blogs
RSS
Naval observatory
Moon
stars
Arcturus
galaxies
planets
A Comet Collision?
Geoff Chester, USNO Public Affairs
in
on May 24, 2022
A disintegrating comet just might give us a show.
Read More
Naval observatory
Moon
planets
Mercury
Venus
Mars
Jupiter
Saturn
stars
Arcturus
Marking May Day
Geoff Chester, USNO Public Affairs
in
on April 27, 2021
We explain the year's second "cross-quarter" day and peer into spring's brightest star.
Read More
Naval observatory
Moon
planets
Mars
Jupiter
Saturn
constellations
Arcturus
Exploring Cracks on the Moon
Geoff Chester, USNO Public Affairs
in
on April 13, 2021
Some of the more interesting lunar formation are featured this week.
Read More
Navy.mil
|
Navy.com
|
Navy FOIA
|
DoD Accessibility/Section 508
|
No Fear Act
|
Open Government
|
Plain Writing Act
USA.gov
|
Veterans Crisis Line
|
DoD Safe Helpline
|
Navy SAPR
|
NCIS Tips
|
Privacy Policy
|
Contact Webmaster
Commander, Naval Meteorology and Oceanography Command | 1100 Balch Blvd. | Stennis Space Center, Mississippi 39529
Official U.S. Navy Website