Time at the meridian through center of old dome US Naval Observatory, Washington, D.C
Washington Mean Time was the time at the meridian through the center of the old dome atop the main building at the old US Naval Observatory at Washington, D.C. This Washington meridian was defined on 28 September 1850 by the United States Congress.[1] The Old Naval Observatory is now on the grounds of the United States Navy Bureau of Medicine and Surgery, southwest of the corner of E and 23rd Streets in Foggy Bottom (north of the Lincoln Memorial). Washington Mean Time was sometimes called Washington Meridian Time. It was never used as the basis of any time zone, although it was the local mean time of the city of Washington before the advent of American time zones on 18 November 1883. It was also used to time astronomical events by users of the American Ephemeris and Nautical Almanac, first published for the year 1855.
In 1897, well after the Old Naval Observatory closed in 1892, the Coast and Geodetic Survey reported that its meridian was 77°3′2.3″ west of Greenwich,[2] which was quoted for the next 50 years in the list of observatories in the Almanac as GMT − 5h8m12.15s. This old Washington meridian was repealed on 22 August 1912.[3] A later version of Washington mean time based on the meridian of the clock room at the exact center of the New Naval Observatory (77°4′2.24″W or GMT − 5h8m16.15s) was still being used in 1950 on a few pages of the American Ephemeris and Nautical Almanac, even though most of its pages used Greenwich Civil Time, the American name for the midnight epoch Greenwich Mean Time. For astronomical purposes, before 1925 a day was considered to start at noon rather than the previous midnight. Thus to convert times of astronomical events before 1925 given in Washington mean time to modern Universal Time it is necessary to add an additional 12 hours beyond the meridian difference from Washington to Greenwich, totalling more than 17 hours.
^9 Stat. 515
^3618 Serial Set 254
^37 Stat. 342
and 23 Related for: Washington Mean Time information
WashingtonMeanTime was the time at the meridian through the center of the old dome atop the main building at the old US Naval Observatory at Washington...
Coordinated Universal Time Local meantime, a form of solar time that corrects the variations of local apparent timeWashingtonMeanTime, the time at the meridian...
Mean Girls is a 2004 American teen comedy film directed by Mark Waters and written by Tina Fey. It stars Lindsay Lohan, Rachel McAdams, Lacey Chabert,...
times it was toward the constellation Aries). Common time on a typical clock (using mean Solar time) measures a slightly longer cycle, affected not only...
of discovery as 11 August 14:40 and 17 August 16:06 Washingtonmeantime respectively). At the time, he was deliberately searching for Martian moons. Hall...
Greenwich MeanTime (GMT), the mean solar time at that location, as an aid to mariners to determine longitude at sea, providing a standard reference time while...
such as FTA. Related probabilistic methods are used to determine system MeanTime Between Failure (MTBF), system availability, or probability of mission...
In mathematics, the geometric mean is a mean or average which indicates a central tendency of a finite set of real numbers by using the product of their...
of time for a few tables (even though Washington's civil time since 1883 had been that of the standard time zone GMT−5 hours (75°W)). Washingtonmean time...
pre-corrected for the equation of time on the date of observation, to form local mean solar time. Noon occurred at different times but time differences between distant...
distribution (RTD), or in terms of its average, known as mean residence time. Residence time plays an important role in chemistry and especially in environmental...
give the time of discovery as 11 August 14:40 and 17 August 16:06 Washingtonmeantime respectively). The telescope used for the discovery was the 26-inch...
though footage on the river was filmed on the Lewis River in southwest Washington. Mean Creek received a limited release in North America in four theaters...
Nominations: SpongeBob SquarePants and Mean Girls Lead the Pack". Playbill. Retrieved March 6, 2024. "Denzel Washington and Jake Gyllenhaal to Star in Othello...
of discovery as 11 August 14:40 and 17 August 16:06 Washingtonmeantime respectively). At the time, he was deliberately searching for Martian moons. Hall...
Standard time is the synchronization of clocks within a geographical region to a single time standard, rather than a local meantime standard. Generally...
Universal Time (UT or UT1) is a time standard based on Earth's rotation. While originally it was mean solar time at 0° longitude, precise measurements...
wrestling, dies at 76". The Washington Post. Archived from the original on January 3, 2019. Retrieved December 18, 2021. "'Mean' Gene Okerlund Injured In...
Waltherus to produce the most accurate tables up to that time, the Rudolphine Tables. He evaluated the mean tropical year as 365 solar days, 5 hours, 48 minutes...
Mean sea level (MSL, often shortened to sea level) is an average surface level of one or more among Earth's coastal bodies of water from which heights...
taken for Earth to revolve around the Sun. Generally, a year is taken to mean a calendar year, but the word is also used for periods loosely associated...
and reputation for tyrannical behavior earned her the nickname Queen of Mean. Leona Helmsley was born Lena Mindy Rosenthal in Marbletown, New York, to...
establish daylight saving time as the standard time in their respective states throughout the calendar year. This would mean that Nevada (except West Wendover)...
Global Information