Health scientists are becoming more and more interested in the citrulline content of watermelon. Citrulline is an amino acid that is commonly converted by our kidneys and other organ systems into arginine (another amino acid). The flesh of a watermelon contains about 250 millligrams of citrulline per cup.
The Julian day or Julian day number (JDN) is the number of days that have passed since the initial epoch defined as noon Universal Time (UT) Monday, January 1, 4713 BC in the Julian calendar. That noon-to-noon day is counted as Julian day 0. Thus the multiples of 7 are Mondays.
1 This epoch was noon UT on January 0, 1900, which is the same as noon UT on December 31, 1899. The DJD was defined by the International Astronomical Union at their meeting in Dublin, Ireland, in 1955.  The Lilian day number is a count of days of the Gregorian calendar and not defined relative to the Julian Date. It is an integer applied to a whole day; day 1 was October 15, 1582, which was the day the Gregorian calendar went into effect.