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List Of Atomic Clocks
This is a list of some experimental laboratory atomic clock An atomic clock is a clock that measures time by monitoring the resonant frequency of atoms. It is based on atoms having different energy levels. Electron states in an atom are associated with different energy levels, and in transitions betwee ...s worldwide. References {{Time measurement and standards Atomic clocks ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atomic Clock
An atomic clock is a clock that measures time by monitoring the resonant frequency of atoms. It is based on atoms having different energy levels. Electron states in an atom are associated with different energy levels, and in transitions between such states they interact with a very specific frequency of electromagnetic radiation. This phenomenon serves as the basis for the International System of Units' (SI) definition of a second:The second, symbol s, is the SI unit of time. It is defined by taking the fixed numerical value of the caesium frequency, \Delta \nu_\mathsf, the unperturbed ground-state hyperfine transition frequency of the caesium 133 atom, to be when expressed in the unit Hz, which is equal to s−1. This definition is the basis for the system of International Atomic Time (TAI), which is maintained by an ensemble of atomic clocks around the world. The system of Coordinated Universal Time, Coordinated Universal Time (UTC) that is the basis of civil time implements ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boulder, Colorado
Boulder is a home rule city that is the county seat and most populous municipality of Boulder County, Colorado, United States. The city population was 108,250 at the 2020 United States census, making it the 12th most populous city in Colorado. Boulder is the principal city of the Boulder, CO Metropolitan Statistical Area and an important part of the Front Range Urban Corridor. Boulder is located at the base of the foothills of the Rocky Mountains, at an elevation of above sea level. Boulder is northwest of the Colorado state capital of Denver. It is home of the main campus of the University of Colorado, the state's largest university. History On November 7, 1861, the Colorado General Assembly passed legislation to locate the University of Colorado in Boulder. On September 20, 1875, the first cornerstone was laid for the first building (Old Main) on the CU campus. The university officially opened on September 5, 1877. In 1907, Boulder adopted an anti- saloon ordinanc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Washington, D
Washington commonly refers to: * Washington (state), United States * Washington, D.C., the capital of the United States ** A metonym for the federal government of the United States ** Washington metropolitan area, the metropolitan area centered on Washington, D.C. * George Washington (1732–1799), the first president of the United States Washington may also refer to: Places England * Washington, Tyne and Wear, a town in the City of Sunderland metropolitan borough ** Washington Old Hall, ancestral home of the family of George Washington * Washington, West Sussex, a village and civil parish Greenland * Cape Washington, Greenland * Washington Land Philippines *New Washington, Aklan, a municipality *Washington, a barangay in Catarman, Northern Samar *Washington, a barangay in Escalante, Negros Occidental *Washington, a barangay in San Jacinto, Masbate *Washington, a barangay in Surigao City United States * Washington, Wisconsin (other) * Fort Washington (other) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Naval Observatory
United States Naval Observatory (USNO) is a scientific and military facility that produces geopositioning, navigation and timekeeping data for the United States Navy and the United States Department of Defense. Established in 1830 as the Depot of Charts and Instruments, it is one of the oldest scientific agencies in the United States, and remains the country's leading authority for astronomical and timing data for all purposes. The observatory is located in Northwest Washington, D.C. at the northwestern end of Embassy Row. It is among the few pre-20th century astronomical observatories located in an urban area; initially located in Foggy Bottom near the city's center, it was relocated to its current location in 1893 to escape light pollution. The USNO has conducted significant scientific studies throughout its history, including measuring the speed of light, observing solar eclipses, and discovering the moons of Mars. Its achievements including providing data for the first ra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Department Of Defense Master Clock
The Department of Defense master clock is the atomic master clock to which time and frequency measurements for the United States Department of Defense are referenced. Located in Washington D.C., the U.S. Naval Observatory master clock is designated as the "DOD Master Clock". It is one of the two standard time and frequency references for the U.S. Government in accordance with Federal Standard 1002-A. The other standard time and frequency reference for the U.S. Government is the National Institute of Standards and Technology (NIST) master clock. In 2018, it was proposed to replace the existing Clock House building it's housed in, designed by Richard Morris Hunt Richard Morris Hunt (October 31, 1827 – July 31, 1895) was an American architect of the nineteenth century and an eminent figure in the history of American architecture. He helped shape New York City with his designs for the 1902 entrance faà ..., with a new facility. The U.S. Naval Observatory also maintai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gannett Company
Gannett Co., Inc. () is an American mass media holding company headquartered in McLean, Virginia, in the Washington, D.C., metropolitan area.Tysons Corner CDP, Virginia ." '' United States Census Bureau''. Retrieved May 7, 2009. It is the largest U.S. newspaper publisher as measured by total daily circulation. Massive layoffs and cessation of newspapers occurrred in November and December, 2022. It owns the |
Fort Collins Coloradoan
The ''Coloradoan'' is a daily newspaper in Fort Collins, Colorado. The ''Coloradoan''s website is updated throughout the day with breaking news and video coverage of community news in Northern Colorado. History Founded by Joseph L. McClelland in 1873 as ''Larimer County Express'', Fort Collins Newspapers Inc. was established in 1937 when Speidel Newspapers acquired the publication known as ''The Express-Courier''. The ''Coloradoan'' moved from its Old Town Fort Collins location to 1212 Riverside Avenue on the city's east side in 1974. Gannett acquired the newspaper when it merged with Speidel in 1977. In 2004, Gannett began construction on a new $6 million facility on property adjacent to their Riverside site. In June 2005, advertising, circulation, human resources, news and technology staffs moved into 1300 Riverside Avenue. The News Director of ''The Coloradoan'' is Eric Larsen, since June 2017. Previous editors include David Greiling, Michael Limon, Bob Moore, Josh Awtry ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Larimer County, Colorado
Larimer County is a county located in the U.S. state of Colorado. As of the 2020 census, the population was 359,066. The county seat and most populous city is Fort Collins. The county was named for William Larimer, Jr., the founder of Denver. Larimer County comprises the Fort Collins, CO Metropolitan Statistical Area. The county is located at the northern end of the Front Range, at the edge of the Colorado Eastern Plains along the border with Wyoming. History Larimer County was created in 1861, and was named after General William Larimer. Unlike that of much of Colorado, which was founded on the mining of gold and silver, the settlement of Larimer County was based almost entirely on agriculture, an industry that few thought possible in the region during the initial days of the Colorado Gold Rush. The mining boom almost entirely passed the county by. It would take the introduction of irrigation to the region in the 1860s to bring the first widespread settlement to the area. E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
WWVB
WWVB is a time signal radio station near Fort Collins, Colorado and is operated by the National Institute of Standards and Technology (NIST). Most radio-controlled clocks in North America use WWVB's transmissions to set the correct time. The 70 kW ERP signal transmitted from WWVB is a continuous 60 kHz carrier wave, the frequency of which is derived from a set of atomic clocks located at the transmitter site, yielding a frequency uncertainty of less than 1 part in 10. A one-bit-per-second time code, which is based on the IRIG "H" time code format and derived from the same set of atomic clocks, is then modulated onto the carrier wave using pulse-width modulation and amplitude-shift keying. A single complete frame of time code begins at the start of each minute, lasts one minute, and conveys the year, day of year, hour, minute, and other information . WWVB is co-located with WWV, a time signal station that broadcasts in both voice and time code on multiple shortwave r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
El Paso County, Colorado
El Paso County is a county located in the U.S. state of Colorado. The 2020 Census recorded its population as 730,395. The Census Bureau's 2020 result indicates it is the most populous county in Colorado, surpassing the City and County of Denver. The county seat is Colorado Springs, the second most populous city in Colorado. El Paso County is included in the Colorado Springs, Colorado, Metropolitan Statistical Area and is located in Colorado's 5th congressional district. History In July 1858, gold was discovered along the South Platte River in Arapahoe County, Kansas Territory. This discovery precipitated the Pike's Peak Gold Rush. Many residents of the mining region felt disconnected from the remote territorial governments of Kansas and Nebraska, so they voted to form their own Territory of Jefferson on October 24, 1859. The following month, the Jefferson Territorial Legislature organized 12 counties for the new territory including El Paso County. El Paso County was named f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Schriever Air Force Base
Schriever Space Force Base, previously Schriever Air Force Base, Falcon Air Force Base, and Falcon Air Force Station, is a base of the United States Space Force located approximately east of Peterson Space Force Base near Colorado Springs in El Paso County, Colorado, United States. History : ''Source: USAF Schriever AFB'' Groundbreaking for what would become Schriever Air Force Base took place in May 1983. It was originally called the Consolidated Space Operations Center (CSOC) during the development phase, and was renamed Falcon Air Force Station upon becoming operational. In July 1985, the 2nd Space Wing was activated at Peterson AFB and in September 1985, the organization relocated to Falcon Air Force Station, and 230 Air Force members, civilian employees, and contractors moved into its 12 new buildings. This wing took operational control of the Air Force Satellite Control Network in a phased system turn over that began in October 1987 and lasted several years. In Jun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
