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XMM-Newton Science Analysis System


selectlib (selectlib-4.77) [xmmsas_20230412_1735-21.0.0]

Times

Times can be expressed in either of the following ways:
form comment example
xxxx-xx-xxTxx:xx:xx[.xxx] combined date-time string 2002-06-03T18:59:01.1
jdxxxxxx.xxx Julian date jd2450850.5
mjdxxxxx.xxx Modified Julian Day mjd50850.5
yxxxx.xxx decimal year number y2002.5
xxx xxx x xx:xx:xx xxxx calendar date Mon Jun 3 18:21:19 2002
x stands for a single decimal digit, jd, mjd, y, T are literal character strings and square brackets denote optional items. The number of shown digits after the decimal point is not significant. In an arithmetic context all given times evaluate to the number of elapsed seconds since the fixed time 1998-01-01T00:00:00 TT.



XMM-Newton SOC -- 2023-04-16