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How are dates in BCE ordered? - History Stack Exchange
For times before 1583 the details should be mutually agreed between the partners who exchanges date values. The order of months in a year does not change, neither does the order of days in a month. January in a particular year is always before December in the same year. So, for your example, 25 January 500 BCE is earlier than 25 December 500 ...
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70-year star in Talmud confusing sailors? - Astronomy Stack Exchange
As described in this article here by Dr Mario Livio: The Talmud (an 1500-2000 year-old Jewish book of laws and traditions) describes how a Rabbi anticipated hs ship getting lost, because “There is a star that appears every 70 years and induces navigation errors. I thought it might appear and cause us to go astray.”.
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Why does the first decade of the 21st century start with 2000?
So year 2010 is the last year of the first decade of the twenty-first century. Roman numerals have historically been used to represent year numbers. Roman numerals do not have a representation for zero so Roman numerals are useful for representing natural numbers but less useful for representing integers.
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the sun - Why is there a year 1 B.C., a year 0, and a year 1 A.D. in ...
The Julian calendar does not include the year 0. Thus the year 1 BCE is followed by the year 1 CE (See: BCE/CE Dating Conventions ). This is awkward for arithmetic calculations. Years in this catalog are numbered astronomically and include the year 0. Historians should note there is a difference of one year between astronomical dates and BCE dates.
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Does a lunar occultation of Mars happen twice a year?
Moon-Mars Occultations occur every 174 to 188 Days. Average worldwide interval (based on 500 years) between occultations is 180 days. In a calendar year, zero to five occultations can occur. Annual occultation doesn't occur on average about once in 15 years. (Source)
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military - How did British aircraft fare against Japanese aircraft ...
To counter the Zero, Spitfire pilots had to adopt a"slash and run" policy and use their faster speed and diving superiority to fight, while avoiding classic dogfights. That Southeast Asia was a lower-priority area also did not help, and it was allocated few Spitfires and other modern fighters compared to Europe, which allowed the Japanese to easily achieve air superiority by 1942.
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What is the proper term for the"year 0"? - History Stack Exchange
8. At the time when the so-called Christian era was introduced, the mathematical concept of zero was not known in Europe. Thus, the year before AD 1 is called 1 BC. However, in modern astronomical and mathematical usage “1 BC” is called the year “0”, “2 BC” is called “-1”, “3 BC” is called “-2”, etc. If you follow this ...
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history - About Year Zero - Astronomy Stack Exchange
2. There is no year zero because the concept of zero arrived to Europe 1200 years later. The concept of something to represent nothing is a bit paradoxical. The history of numbers is chock full of paradoxical thinking. This includes numbers that aren't numbers (negative numbers), numbers that don't make a bit of sense (irrational numbers), and ...
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Date and Time of Year given Sun's Right Ascension
I want to determine OPTIMAL date, time (and location) to observe a particular star (i.e. RA and DEC known). I impose 2 conditions: (i) star is 'CULMINATING' (i.e. pasing thru local meridian), so Local Siderial Time (LST) = RA (star) + HA (star) = RA (star), and (ii) it's midnight so LST = RA (sun) + HA (sun) = RA (sun) + 12 hr. Equating both ...
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Was the symbol post-classical Mayans used to represent zero really ...
The earliest source I can find that make the connection between the pointed, oval-shape symbol for zero and seashells is Animal Figures in the Maya Codices (Tozzer and Allen, 1910):"the glyphs for various molluscs which are used not to represent the shell but to give the value of zero to the numerical calculations."
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