DateTime::jd off by 12 hours(?)
I am deeply reluctant to file a bug against something so fundamental as DateTime, and wonder whether I might have missed something, but:
When passed an integral value, DateTime::jd returns a DateTime object whose time is set to midnight GMT:
puts DateTime.jd 2455972
The WikiPedia entry for "Julian Day" reads, in part: "Julian day is used in the Julian date (JD) system of time measurement for scientific use by the astronomy community, presenting the interval of time in days and fractions of a day since January 1, 4713 BC Greenwich noon."
It therefore seems to me that a whole number of days since that time would itself necessarily fall on Greenwich noon.
Please feel free to tell me that I'm missing something blindingly obvious.