On this day in the Star Trek universe:

Star Trek: The Next Generation (1988)

Star Trek: Enterprise (2003)

Star Trek: The Next Generation

Season 1. Episode 21.

Episode entitled: Symbiosis.

Released April 16, 1988.

Directed by Win Phelps.

Written by Robert Lewin, Richard Manning, Hans Beimler, Hannah Louise Shearer, Tracy Tormé.

Created by Gene Roddenberry.

Music by Dennis McCarthy.

Cast: Patrick Stewart, Jonathan Frakes, LeVar Burton, Denise Crosby, Michael Dorn, Gates McFadden, Marina Sirtis, Brent Spiner, Wil Wheaton, Judson Scott, Merritt Butrick, Richard Lineback, Kimberley Farr, Majel Barrett, James G. Becker, Susan Duchow, Shana Golden, Tim McCormack, Lorine Mendell, Kenneth Tigar.

Star Trek: Enterprise

Season 2. Episode 20.

Episode entitled: Horizon.

Released April 16, 2003.

Directed by James Contner.

Written by André Bormanis.

Created by Rick Berman, Brannon Braga.

Based on Star Trek, created by Gene Roddenberry.

Opening theme song: Faith of the Heart, performed by Russell Watson.

Closing theme: Archer's Theme, by Dennis McCarthy.

Music by Mark McKenzie.

Cast: Scott Bakula, John Billingsley, Jolene Blalock, Dominic Keating, Anthony Montgomery, Linda Park, Connor Trinneer, Joan Pringle, Corey Mendell Parker, Nicole Forester, Adam Paul, Philip Anthony-Rodriguez, Ken Feinberg, Alexandrea Ortiz, Colin Clive, Mark Correy, Evan English, Nikki Flux, Dwight Frye, Glen Hambly, Scott Sterling Hill, Aldric A. Horton, Roy Joaquin, Amina Julianna, John Jurgens, Boris Karloff, Aouri Makhlouf, Marnie Martin, Michael McAdam, Bobby Pappas, Lidia Sabljic, Monika Spruch, Warren Tabata, Scott L. Treger.