title: Convert unix timestamp to julian
body: <p>How can I convert from a unix timestamp (say 1232559922) to a fractional julian date (2454853.03150).</p>
  
  <p>I found a website ( <a href="http://aa.usno.navy.mil/data/docs/JulianDate.php" rel="noreferrer">http://aa.usno.navy.mil/data/docs/JulianDate.php</a> ) that performs a similar calculation but I need to do it programatically. </p>
  
  <p>Solutions can be in C/C++, python, perl, bash, etc...</p>