A report was submitted to the "Transactions of the Royal Society of Canada," dated 10 May 1894; on the "Unification of the Astronomical, Civil and Nautical Days"; which stated that: :civil day- begins at midnight and ends at midnight following, :astronomical day- begins at noon of civil day and continue until following noon, and :nautical day- concludes at noon of civil day, starting at preceding noon.
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Over shorter timescales, there are a variety of practices for defining when each day begins. In ordinary usage, the civil day is reckoned by the midnight epoch, that is, the civil day begins at midnight. But in older astronomical usage, it was usual, until January 1, 1925, to reckon by a noon epoch, 12 hours after the start of the civil day of the same denomination, so that the day began when the mean sun crossed the meridian at noon.H. C. Wilson, "Change of astronomical time", Popular Astronomy, 33 (1925): 1-2.
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In order to keep the civil day aligned with the apparent movement of the Sun, a day according to Coordinated Universal Time (UTC) can include a negative or positive leap second. Therefore, although typically 86,400 SI seconds in duration, a civil day can be either 86,401 or 86,399 SI seconds long on such a day. Leap seconds are announced in advance by the International Earth Rotation and Reference Systems Service (IERS), which measures the Earth's rotation and determines whether a leap second is necessary.
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The civil day (dies civilis) ran from midnight (media nox) to midnight. The date of birth of children was given as this period, as is the case today. It was divided into the following parts: 1. Media nox, 2. Mediae noctis inclinatio, 3.
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Civil grew up in a Haitian-American family in Elizabeth, New Jersey. She attended Elizabeth High School, then Union County College in New Jersey.Blackwell, Ashley. "Karen Civil Receives Key To The City of Elizabeth, NJ During 'Live Civil Day'", Parle magazine, June 28, 2017.
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In April 2017, Civil opened her Live Civil Computer Lab at the House Of Hope Orphanage in Haiti and donated 20 computers to the children. In August 2017, Civil worked with shoe company K-Swiss to produce a line of shoes. Civil had, as of December 2017, hosted an event called "Karen Civil Day" three times. In May 2018, it was announced that Karen Civil would host the series Good Looking Out on Complex Networks.
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This agreed with the civil Greenwich Mean Time used on the island of Great Britain since 1847. In contrast astronomical GMT began at mean noon, i.e. astronomical day X began at noon of civil day X. The purpose of this was to keep one night's observations under one date. The civil system was adopted as of 0 hours (civil) 1 January 1925. Nautical GMT began 24 hours before astronomical GMT, at least until 1805 in the Royal Navy, but persisted much later elsewhere because it was mentioned at the 1884 conference.
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The field of Jyotisha deals with ascertaining time, particularly forecasting auspicious day and time for Vedic rituals. The field of Vedanga structured time into Yuga which was a 5-year interval, divided into multiple lunisolar intervals such as 60 solar months, 61 savana months, 62 synodic months and 67 sidereal months. A Vedic Yuga had 1,860 tithis (, dates), and it defined a savana-day (civil day) from one sunrise to another. The Rigvedic version of Jyotisha may be a later insertion into the Veda, states David Pingree, possibly between 513 and 326 BCE, when Indus valley was occupied by the Achaemenid from Mesopotamia.
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Just like months, the Hindu calendar has two measures of a day, one based on the lunar movement and the other on solar. The solar day or civil day, called divasa ( दिवस), has been what most Hindus traditionally use, is easy and empirical to observe, by poor and rich, with or without a clock, and it is defined as the period from one sunrise to another. The lunar day is called tithi (तिथि), and this is based on complicated measures of lunar movement. A lunar day or tithi may, for example, begin in the middle of an afternoon and end next afternoon.
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This location was chosen because by 1884 two-thirds of all nautical charts and maps already used it as their prime meridian. The conference did not adopt Fleming's time zones because they were outside the purpose for which it was called, which was to choose a basis for universal time (as well as a prime meridian). During the period between 1848 and 1972, all of the major countries adopted time zones based on the Greenwich meridian. In 1935, the term Universal Time was recommended by the International Astronomical Union as a more precise term than Greenwich Mean Time, because GMT could refer to either an astronomical day starting at noon or a civil day starting at midnight.
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The clasps covered a variety of actions, from boat service to single-ship actions, to larger naval engagements, including major fleet actions such as the Battle of Trafalgar. In all, 20,933 medals were awarded, 15,577 with a single clasp. Some discrepancies between the dates of the medals and actual actions are due to the Royal Navy's practice of dating, in which the day officially began at noon. Until 11 October 1805 (when the Admiralty ordered that "the calendar or civil day is to be made use of, beginning at midnight") ships' logs were kept in nautical time and written up at midday, so that a day's entry consisted of the proceedings for the afternoon of the day before and morning of that day.
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For civil purposes, a common clock time is typically defined for an entire region based on the local mean solar time at a central meridian. Such time zones began to be adopted about the middle of the 19th century when railroads with regularly occurring schedules came into use, with most major countries having adopted them by 1929. As of 2015, throughout the world, 40 such zones are now in use: the central zone, from which all others are defined as offsets, is known as UTC±00, which uses Coordinated Universal Time (UTC). The most common convention starts the civil day at midnight: this is near the time of the lower culmination of the Sun on the central meridian of the time zone.
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When all astronomers decided to start their astronomical days at midnight to conform to the beginning of the civil day, on , it was decided to keep Julian days continuous with previous practice, beginning at noon. During this period, usage of Julian Day Numbers as a neutral intermediary when converting a date in one calendar into a date in another calendar also occurred. An isolated use was by Ebenezer Burgess in his 1860 Translation of the Surya Siddhanta wherein he stated that the beginning of the Kali Yuga era occurred at midnight at the meridian of Ujjain at the end of the 588,465th day and the beginning of the 588,466th day (civil reckoning) of the Julian Period, or between or .Burgess 1860Burgess was furnished these Julian days by US Nautical Alamanac Office.
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Sun and Moon, Hartmann Schedel's Nuremberg Chronicle, 1493 For most diurnal animals, the day naturally begins at dawn and ends at sunset. Humans, with their cultural norms and scientific knowledge, have employed several different conceptions of the day's boundaries. In the Hebrew Bible, Genesis 1:5 defines a day in terms of "evening" and "morning" before recounting the creation of a sun to illuminate it: "And God called the light Day, and the darkness he called Night. And the evening and the morning were the first day." Common convention among the ancient Romans,See Plutarch, Quaestiones Romanae, 84. ancient Chineses:zh:清史稿/卷48: 起子正，盡夜子初。 and in modern times is for the civil day to begin at midnight, i.e. 00:00, and to last a full 24 hours until 24:00 (i.e. 00:00 of the next day).
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The Canadian Pacific Railway was among the first organizations to adopt the 24-hour clock, at midsummer 1886.The London Times reports on a timetable using the 24-hour clock on a trip from Port Arthur, Ontario: At the International Meridian Conference in 1884, American lawyer and astronomer Lewis M. Rutherfurd proposed: > That this universal day is to be a mean solar day; is to begin for all the > world at the moment of midnight of the initial meridian coinciding with the > beginning of the civil day and date of that meridian, and is to be counted > from zero up to twenty-four hours. This resolution was adopted by the conference. The Shepherd Gate Clock with Roman numerals up to XXIII (23) and 0 for midnight, in Greenwich A report by a government committee in the United Kingdom noted Italy as the first country among those mentioned to adopt 24-hour time nationally, in 1893.
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