I'd be happy with creating a DateTime object from julian, but I don't see that as one of the options (one can go the other direction).
I tried something like 
my $dt = DateTime->today;
say $dt, " = ", $dt->jd;
$dt->subtract(days => $dt->jd, hours => 12); # days implicitly truncat
+ed to int
say $dt, " = ", $dt->jd;

[download]
and came out with 
2015-06-29T00:00:00 = 2457202.5
-4713-11-24T12:00:00 = 0

[download]
So, 
my $jd_to_convert = 2457205.09613609;
my $dt = DateTime->new(year => -4713, month => 11, day =>24, hour => 1
+2)->add(days => $jd_to_convert);
say $dt, " = ", $dt->jd;

[download]
gives 
2015-07-01T12:00:00 = 2457205

[download]
(With Time::Piece the method would be the same)

Now you just need to convert the fractional part to h m s...

Update: Hah! DateTime accepts fractional hours, exactitude about 0.15 sec on my system
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" gre
+gorian calendar
    my $dt = DateTime->new(year => -4713, month => 11, day =>24, hour 
+=> 12, time_zone => DateTime::TimeZone->new( name => 'UTC' ))->add(da
+ys => $days);
    $dt->add(hours => 24 * ($jd_to_convert - $days));
    return $dt; # 2017-06-13 added this line for clarity
}

[download]
[further update: added comments and time zone, as JD is relative to UTC]

In reply to Re: getting a utc value from julian date by soonix
in thread getting a utc value from julian date by Aldebaran

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