 Makropulos is the name from Karel Čapek's play Věc Makropulos (The Makropulos Affair).XO-5b was the fifth hot Jupiter transiting planet discovered by the XO Project and was identified as a possible candidate extrasolar planet from two seasons of observations, November 2003 to March 2004 and November 2004 to March 2005.Follow-up photometry was provided by the extended team, a collaboration of professional and amateur astronomers.