The character of Tommy Solomon is played by actor Joseph Gordon-Levitt. In this interview he discusses the role of Tommy Solomon and his experience of being part of the show:
Tommy arrives on Earth as the oldest member of the mission yet he is assigned the role of Dick's teenage son; Sally and Harry being his aunt and uncle respectively.
He is third-in-command, which effectively means last because only Harry ranks below him. This is strange because Tommy is clearly the most intelligent of the group. Ironically though, this facilitates his human role. It is generally the case (in TV sitcoms anyway) that the youngest member of a dysfunctional family turns out to be the most stable intellectually - Lisa Simpson's male equivalent if you like.
If being an old man in an adolescent boy's body isn't bad enough, Tommy also has to endure all the other growing pains and rites of passage that form part of Earth customs. He enrols at High School where he excels academically, has a few romantic trysts and succeeds in making friends with other students.
On arriving on Earth, the first obstacles that Tommy has to surmount are of a teenage hormonal kind. His first experience of this comes from being in the same room as Nina. Later he is barely able to contain himself after watching a girls' volleyball game.
He has two important loves during his six year stint. His first girlfriend is August, who is smart and intelligent like Tommy, but also cold, domineering and reserved. Their relationship peters out. He later starts dating the bubbly and lovely Alissa, who is far more tolerant and forgiving; although that relationship also comes to an end even before the mission (and the series) ends.
During the sixth and final season Joseph Gordon-Levitt had left the show's regular cast, becoming more of a recurring character. It was written into the storyline that Tommy goes off to college to facilitate this move.
Both the actor, Joseph Gordon-Levitt and the character of Tommy Solomon age dramatically during the show's run. He grows up on screen and the change is dramatic. This of course is to be expected given that Gordon-Levitt would have been no more than 15 when the show first aired in 1996.
In the early episodes Tommy is constantly referred to as 'looking like a girl' on account of his long hair - (this was the Grunge era after all). When around the third season he finally gets a haircut, the other aliens purport not to recognise him. They only accept that he is Tommy when he is able to correctly answer the question - 'Are we aliens?'