Converting from Julian Date to Unix Epoch time is trivial:

my $jd = '2457206.13659';
say scalar gmtime(($jd -2440587.5) * 86400)';
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Output:

Thu Jul  2 15:16:41 2015
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If you want a more convenient way to represent your Julian Date's, have a look at Time::Moment (I'm biased since I'm the author of Time::Moment)

-- chansen