Difference Between Dates and Optional Times
Start Date:   ±Y  M  D Start Time:   H M S
Calendar Mode:   Julian            Gregorian
End Date:   ±Y  M  D End Time:   H M S 
Calendar Mode = Gregorian


Start Date/Time   = 2019 August 17 Sat 12:00:00.000
Julian Date       = 2458713
Julian Day Number = 2458713

————————————————————
2019          August

Su Mo Tu We Th Fr Sa
             1  2  3 
 4  5  6  7  8  9 10 
11 12 13 14 15 16 17 
18 19 20 21 22 23 24 
25 26 27 28 29 30 31
————————————————————


*******************************************************


End Date/Time     = 2019 August 17 Sat 12:00:00.000
Julian Date       = 2458713
Julian Day Number = 2458713

————————————————————
2019          August

Su Mo Tu We Th Fr Sa
             1  2  3 
 4  5  6  7  8  9 10 
11 12 13 14 15 16 17 
18 19 20 21 22 23 24 
25 26 27 28 29 30 31
————————————————————

DIFFERENCE BETWEEN DATES AND TIMES
= (JD2 − JD1) = 0 d
= 0 Gregorian yr
=  0d  00h 00m 00s