> > have no leap seconds. Astronomers appear to avoid > > using MJD altogether. > > Good grief. MJD is used widely in astronomy, for example in variablility > studies where you want a real number to represent time rather than deal > with the complications of parsing a date. It tends to be written into the > FITS header of practically every data file observed. > > Pete.
OK, my information was dated. It was my impression from reading lots of metrology papers and a few astronomy papers that the timing folks almost always use MJD while astronomers almost always use JD. There was also something about the IAU and [mis]use of MJD. I see now the deeper IAU MJD story is covered at: http://hbar.phys.msu.ru/gorm/ahist/juldate.htm and RESOLUTION B1: ON THE USE OF JULIAN DATES http://www.iers.org/iers/earth/resolutions/UAI_b1.html http://www.iers.org/MainDisp.csl?pid=98-110 Thanks for the clarification. /tvb