Convert Julian Date to YYYY,MM,DD Format

@Manasa1801Jan 19.2021

I am trying to convert Julian Date to YYYY,MM,DD format so that the converted date can be displayed using Full Calender IO (This third party library accepts normal dates and cannt display Julian Date in Calender), Anyone has idea on how to convert Julian date to YYYY,MM,DD format in Javascript? Please help

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JavaScript

@daveyerwinJan 19.2021 — #@Manasa1801#1626936

Where does this Julian Date come from ?

@JMRKERJan 19.2021 — #Quick google search and a little modification results in this possibility.

See code comments for references.

<i>
 </i>&lt;!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"&gt; 
 &lt;HTML&gt;
 &lt;BODY&gt;
 &lt;pre id='demo'&gt;&lt;/pre&gt;
 
 &lt;script language="JavaScript"&gt;
 /* Origin of Modified Julian Date (MJD) is 00:00 November 17, 1858 of
 the Gregorian calendar
 Internal JavaScript built in Date object internal time value 0
 milliseconds (ms) is 00:00 January 1, 1970, UT,
 equal to MJD 40587
 Internal value of MJD origion should be
 negative 40587 days * 86,400,000 milliseconds per day =
 3,506,716,800,000 ms
 */
 // Modified from: https://stackoverflow.com/questions/29627533/conversion-of-julian-date-number-to-normal-date-utc-in-javascript
 // for question from: https://www.webdeveloper.com/d/392446-convert-julian-date-to-yyyymmdd-format
 var originMJD = -3506716800000, str = '';
 str += "Test creation of date object containing origin of MJD.n";
 str += new Date(-3506716800000).toUTCString();
 str += " should be Wed, 17 Nov 1858 00:00:00 UT.nn";
 
 //Given an MJD display the Gregorian calendar date and time.
 var inMJD = 57115;
 var inInternal = (inMJD * 86400000) + originMJD;
 str += <span><code>Input MJD is ${inMJD}.n</code></span>;
 str += "Equivalent Gregorian calendar date and time is ";
 str += new Date(inInternal).toUTCString()+".";
 document.getElementById('demo').innerHTML = str;
 
 const month2number = (info) =&gt; {
 let month = [0,'Jan','Feb','Mar','Apr','May','Jun','Jul','Aug','Sep','Oct','Nov','Dec'].indexOf(info);
 return month.toString().padStart(2,'0');
 }
 
 const Julian2Date = (jdate) =&gt; {
 var originMJD = -3506716800000;
 //  var orig = new Date(-3506716800000).toUTCString();  alert(orig);  // for testing purposes only
 var ndate = (jdate * 86400000) + originMJD;
 let dateStr = new Date(ndate).toUTCString().split(' ');  // as long display
 let [dd,mm,yyyy] = [dateStr[1],month2number(dateStr[2]),dateStr[3]];
 return <span><code>${yyyy}/${mm}/${dd}</code></span>;
 }
 
 alert(Julian2Date(0));
 alert(Julian2Date(57115));
 &lt;/script&gt;
 &lt;/BODY&gt;
 &lt;/HTML&gt;

@JennieMillerJan 21.2021 — #there is a tool to convert Julian Date format.

@JMRKERJan 21.2021 — #@JennieMiller#1626991 How does your answer help if you don't provide a link or reference to your "tool"?

@daveyerwinJan 21.2021 — #I would like to know where this Julian Date date comes from ?

I would suspect at some point a date in text was converted to Julian Date.

@marksmith121Jan 25.2021 — #We refer to a yyddd date format (yy = year, ddd=day) as a 'Julian Date' - this is the common term for such a date in mainframe and other circles. However technically, a Julian date can mean different things. Astronomers refer to a Julian date as the number of days since the beginning of the Julian Period (January 1, 4713 BC). The Smithsonian Astrophysical Observatory introduced the 'Modified Julian Date' to record the orbit of the Sputnik satellite in 18 bits.

@johncarryJan 28.2021 — #there is a tools to convert. search in google.

@tome1122Feb 02.2021 — #@johncarry#1627305 If you know about this so please send link inbox.

Convert Julian Date to YYYY,MM,DD Format

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