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Timekeeping On The Moon
Timekeeping on the Moon is an issue of synchronized human activity on the Moon and contact with such. The two main differences to timekeeping on Earth are the length of a day on the Moon, being the lunar day or lunar month, observable from Earth as the lunar phases, and the rate at which time progresses, with 24 hours on the Moon being 58.7 microseconds (0.0000587 seconds) faster, resulting from gravitational time dilation due to the different masses of the Moon and Earth. History Buzz Aldrin wearing an Omega Speedmaster watch during alt=an astronaut with short hair and wearing a watch, flight suit and commset looks at the camera The technology used for the timekeeping device">Apollo 11 mission in 1969">alt=an astronaut with short hair and wearing a watch, flight suit and commset looks at the camera The technology used for the timekeeping devices deployed to the Moon have varied over the decades. Several Omega Speedmasters have been on the Moon, synched to Central Stand ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Moon
The Moon is Earth's only natural satellite. It Orbit of the Moon, orbits around Earth at Lunar distance, an average distance of (; about 30 times Earth diameter, Earth's diameter). The Moon rotation, rotates, with a rotation period (lunar day) that is synchronized to its orbital period (Lunar month#Synodic month, lunar month) of 29.5 Earth days. This is the product of Earth's gravitation having tidal forces, tidally pulled on the Moon until one part of it stopped rotating away from the near side of the Moon, near side, making always the same lunar surface face Earth. Conversley, the gravitational pull of the Moon, on Earth, is the main driver of Earth's tides. In geophysical definition of planet, geophysical terms, the Moon is a planetary-mass object or satellite planet. Its mass is 1.2% that of the Earth, and its diameter is , roughly one-quarter of Earth's (about as wide as the contiguous United States). Within the Solar System, it is the List of Solar System objects by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Feet Per Second
The foot per second (plural feet per second) is a unit of both speed (scalar) and velocity (vector quantity, which includes direction). It expresses the distance in feet (ft) traveled or displaced, divided by the time in seconds (s). The corresponding unit in the International System of Units The International System of Units, internationally known by the abbreviation SI (from French ), is the modern form of the metric system and the world's most widely used system of measurement. It is the only system of measurement with official s ... (SI) is the meter per second. Abbreviations include ft/s, fps, and the scientific notation ft s−1. Conversions See also * Foot per second squared, a corresponding unit of acceleration. * Feet per minute References Units of velocity Customary units of measurement in the United States {{physics-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Satellite
A satellite or an artificial satellite is an object, typically a spacecraft, placed into orbit around a celestial body. They have a variety of uses, including communication relay, weather forecasting, navigation ( GPS), broadcasting, scientific research, and Earth observation. Additional military uses are reconnaissance, early warning, signals intelligence and, potentially, weapon delivery. Other satellites include the final rocket stages that place satellites in orbit and formerly useful satellites that later become defunct. Except for passive satellites, most satellites have an electricity generation system for equipment on board, such as solar panels or radioisotope thermoelectric generators (RTGs). Most satellites also have a method of communication to ground stations, called transponders. Many satellites use a standardized bus to save cost and work, the most popular of which are small CubeSats. Similar satellites can work together as groups, forming constellatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spacecraft
A spacecraft is a vehicle that is designed spaceflight, to fly and operate in outer space. Spacecraft are used for a variety of purposes, including Telecommunications, communications, Earth observation satellite, Earth observation, Weather satellite, meteorology, navigation, space colonization, Planetary science, planetary exploration, and Space transport, transportation of Human spaceflight, humans and cargo spacecraft, cargo. All spacecraft except single-stage-to-orbit vehicles cannot get into space on their own, and require a launch vehicle (carrier rocket). On a sub-orbital spaceflight, a space vehicle enters space and then returns to the surface without having gained sufficient energy or velocity to make a full Geocentric orbit, Earth orbit. For orbital spaceflights, spacecraft enter closed orbits around the Earth or around other Astronomical object, celestial bodies. Spacecraft used for human spaceflight carry people on board as crew or passengers from start or on orbit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reuters
Reuters ( ) is a news agency owned by Thomson Reuters. It employs around 2,500 journalists and 600 photojournalists in about 200 locations worldwide writing in 16 languages. Reuters is one of the largest news agencies in the world. The agency was established in London in 1851 by Paul Reuter. The Thomson Corporation of Canada acquired the agency in a 2008 corporate merger, resulting in the formation of the Thomson Reuters Corporation. In December 2024, Reuters was ranked as the 27th most visited news site in the world, with over 105 million monthly readers. History 19th century Paul Julius Reuter worked at a book-publishing firm in Berlin and was involved in distributing radical pamphlets at the beginning of the Revolutions of 1848. These publications brought much attention to Reuter, who in 1850 developed a prototype news service in Aachen using homing pigeons and electric telegraphy from 1851 on, in order to transmit messages between Brussels and Aachen, in what today is Aa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Space Race
The Space Race (, ) was a 20th-century competition between the Cold War rivals, the United States and the Soviet Union, to achieve superior spaceflight capability. It had its origins in the ballistic missile-based nuclear arms race between the two nations following World War II and the onset of the Cold War. The technological advantage demonstrated by spaceflight achievement was seen as necessary for national security, particularly in regard to intercontinental ballistic missile and Reconnaissance satellite, satellite reconnaissance capability, but also became part of the cultural symbolism and ideology of the time. The Space Race brought pioneering launches of artificial satellites, robotic landers to the Moon, Venus, and Mars, and human spaceflight in low Earth orbit and ultimately to the Moon. Public interest in space travel originated in the 1951 publication of a Soviet youth magazine and was promptly picked up by US magazines. The competition began on July 30, 1955, when ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
China Standard Time
The time in China follows a single standard UTC offset, time offset of UTC+08:00, where Beijing is located, even though the country spans five geographical time zones. It is the largest sovereign nation in the world that officially observes only one time zone. The nationwide standardized time is named Beijing Time (BJT; ) domestically and China Standard Time (CST) internationally. Daylight saving time has not been observed since 1991. China Standard Time (UTC+8) is consistent across Mainland China, Hong Kong Time, Hong Kong, and Macau Standard Time, Macau. It is also equivalent with Time in Taiwan, Taiwan, Philippine Standard Time, Philippines, Singapore Standard Time, Singapore, Time in Brunei, Brunei, most of Time in Mongolia, Mongolia, Time in Malaysia, Malaysia, Irkutsk Time of Russia, Time in Australia, Western Australia, and Time in Indonesia, Central Indonesia. History In the 1870s, the Shanghai Xujiahui Observatory was constructed by a French Catholic missionary. In 1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Central Time Zone
The North American Central Time Zone (CT) is a time zone in parts of Canada, the United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ..., Mexico, Central America, and a few Caribbean Islands, Caribbean islands. In parts of that zone (20 states in the US, three provinces or territories in Canada, and several border municipalities in Mexico), the Central Time Zone is affected by two time designations yearly: Central Standard Time (CST) is observed from the first Sunday in November to the second Sunday in March. It is UTC−06:00, six hours behind Coordinated Universal Time (UTC) and designated internationally as UTC−6. From the second Sunday in March to the first Sunday in November the same areas observe daylight saving time (DST), creating the designation of Central ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apollo Program
The Apollo program, also known as Project Apollo, was the United States human spaceflight program led by NASA, which Moon landing, landed the first humans on the Moon in 1969. Apollo followed Project Mercury that put the first Americans in space. It was conceived in 1960 as a three-person spacecraft during President Presidency of Dwight D. Eisenhower, Dwight D. Eisenhower's administration. Apollo was later dedicated to President John F. Kennedy's national goal for the 1960s of "landing a man on the Moon and returning him safely to the Earth" in an address to United States Congress, Congress on May 25, 1961. It was the third American human spaceflight program to fly, preceded by Project Gemini conceived in 1961 to extend spaceflight capability in support of Apollo. Kennedy's goal was accomplished on the Apollo 11 mission when astronauts Neil Armstrong and Buzz Aldrin landed their Apollo Lunar Module (LM) on July 20, 1969, and walked on the lunar surface, while Michael Collins ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Space
Space is a three-dimensional continuum containing positions and directions. In classical physics, physical space is often conceived in three linear dimensions. Modern physicists usually consider it, with time, to be part of a boundless four-dimensional continuum known as '' spacetime''. The concept of space is considered to be of fundamental importance to an understanding of the physical universe. However, disagreement continues between philosophers over whether it is itself an entity, a relationship between entities, or part of a conceptual framework. In the 19th and 20th centuries mathematicians began to examine geometries that are non-Euclidean, in which space is conceived as '' curved'', rather than '' flat'', as in the Euclidean space. According to Albert Einstein's theory of general relativity, space around gravitational fields deviates from Euclidean space. Experimental tests of general relativity have confirmed that non-Euclidean geometries provide a bet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Time Standard
A time standard is a specification for measuring time: either the rate at which time passes or points in time or both. In modern times, several time specifications have been officially recognized as standards, where formerly they were matters of custom and practice. An example of a kind of time standard can be a time scale, specifying a method for measuring divisions of time. A standard for civil time can specify both time intervals and time-of-day. Standardized time measurements are made using a clock to count periods of some period changes, which may be either the changes of a natural phenomenon or of an artificial machine. Historically, time standards were often based on the Earth's rotational period. From the late 18 century to the 19th century it was assumed that the Earth's daily rotational rate was constant. Astronomical observations of several kinds, including eclipse records, studied in the 19th century, raised suspicions that the rate at which Earth rotates is gradually ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Office Of Science And Technology Policy
The Office of Science and Technology Policy (OSTP) is a department of the United States government, part of the Executive Office of the President of the United States, Executive Office of the President (EOP), established by United States Congress on May 11, 1976, with a broad mandate to advise the President of the United States, president on the effects of Science and technology in the United States, science and technology on domestic and international affairs. The director of this office is traditionally colloquially known as the Science Advisor to the President, science advisor to the president. A recent appointed director was mathematician and geneticist Eric Lander who was sworn in on June 2, 2021. Lander resigned February 18, 2022, following allegations of misconduct. On February 16, 2022, the Biden administration announced that deputy director Alondra Nelson would serve as acting director and former National Institutes of Health (NIH) director Francis Collins would serve a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
