#! /usr/bin/perl
use warnings;
use strict;
use 5.010;
use DateTime;
use DateTime::TimeZone;

my $begin = 2457205.09272861;
my $middle = 2457205.09613609;
my $end = 2457205.09954643;

my $dt1 = jd2dt($begin);
say "date1 is $dt1";
my $dt2 = jd2dt($middle);
say "date2 is $dt2";
my $dt3 = jd2dt($end);
say "date3 is $dt3";
my $dur = $dt3-$dt1;
say "dur is $dur";


sub jd2dt {
	# convert JD to DateTime
	my $jd_to_convert = shift;
	my $days = int $jd_to_convert;
	# that odd date is "julian day zero", converted to "proleptic" gregorian calendar
	my $dt = DateTime->new(year => -4713, month => 11, day =>24, hour => 12, time_zone => DateTime::TimeZone->new( name => 'UTC' ))->add(days => $days);
	$dt->add(hours => 24 * ($jd_to_convert - $days));
	say "date is $dt";
}