(written from a Production point of view)
Marston Smith (born 14 January 1952; age 68) is a professional cellist who appeared as a cello playing command ensign in the Star Trek: The Next Generation third season episode "Sarek".  He received no credit for his appearance and music contribution.
Born in Fort Worth, Texas, USA, Smith attended Santa Monica High School and the University of California in Santa Barbara. He studied cello performance at the Stony Brook State University of New York. Today, Smith is residing in Malibu, California.
As a professional cellist, Smith released over sixteen albums with his music. On two of them he collaborated with fellow musician, pianist and actor John O'Hurley such as the 2005 album "Peace of Our Minds". He performed with Stevie Wonder, Neil Diamond, The Beach Boys, KISS, Barry Manilow, and Rod Stewart and opened concerts and shows for Michael Bublé and The B-52's. Smith worked on the music for films such as the horror film Alligator (1980), the music drama The Jazz Singer (1980), the romance An Officer and a Gentleman (1982), the drama Out of Africa (1985), the thriller El secreto de sus ojos (2009), and the thriller Miss Bala (2011) and for television series such as The Simpsons (2003). He also performed at the wedding of Elizabeth Taylor and Larry Fortensky in October 1991. 
Smith appears live around the world including casinos in Las Vegas, shows of Cirque du soleil, and corporate events for Google, eBay, Microsoft, Toyota, Warner Bros., and Disney. Other appearances include the talk shows Later with Greg Kinnear (1999) and The Tonight Show with Jay Leno (2012) as well as the fantasy series Scary Tales (2011).