(written from a Production point of view)
Colonel Terry W. Virts, Jr. (born 1 December 1967; age 50) is a NASA astronaut who made a cameo appearance as Ensign T. Virts in the last Star Trek: Enterprise episode "These Are the Voyages...". He received no credit and appeared alongside fellow astronaut E. Michael Fincke in a scene placed in main engineering.
Virts was born in Baltimore, Maryland and is married to Stacy Hill. The couple has two children. Virts attended the Oakland Mills High School in Columbia, Maryland and graduated in 1985. Due to an exchange program from the United States Air Force Academy he attended the Ecole d l'Air, the French Air Force Academy and graduated in 1989, with the rank of a second lieutenant. He has started his pilot career at the Williams Air Force Base in Arizona in 1990 and joined several flight teams until his selection as a member of the 18th group of NASA astronaut candidates in July 2000.
Virts joined several space mission, has worked as a CAPCOM from Expedition 8 through 15, and is currently working as the lead Ascent and Entry CAPCOM. In February 2010, Virts went into space for the first time, piloting the shuttle Endeavor on a mission to resupply the International Space Station.
Virts visited alongside E. Michael Fincke the set of ENT during vacation and was offered a role in the last episode. As a long time Star Trek fan, he stated that Star Trek: The Original Series and the Star Trek films had an impact on him and motivated him to pursue a NASA career. 
Virts was interviewed for the 2009 release of the DVD box Star Trek: Original Motion Picture Collection and told about his connection to NASA and Star Trek in the special feature "Star Trek Honors NASA".