Why were all the Babylon-5 actors 40 and older?

For no particular reason, I was reading up on all the Babylon-5 actors, and realized almost all of them were at least 40 years old. Was there any particular reason for that, or just coincidence? Were the writers/directors going for a certain “maturity” or something?

Don’t know if there was any particular intent behind the casting, but the characters, mostly being Commanders or Captains, Ambassadors, etc., might tend to be in their 40s anyways, at least during peacetime. I make this assumption while also assuming that it would take several years to train them in the various necessary skills needed in space.

Failing that, I’m gonna say it’s Cosmic Radiation™ that makes the characters LOOK like they’re in their 40’s, thus necessitating actors in that age range.

Straczynski wanted the characters to have some backstory and history, and the events prior to the series took place some years prior to it, so it was logical that the characters were older.

I can understand the character’s having backstories, yet the Earth/Mimbari war wasn’t that long before the events of the show. But for instance, Garabaldi’s little security side-kick is also forty-something. Leeta the telepath was 40-ish. I don’t see why Ivanova had to be 40-ish, her character was a youngish, brash up-and-coming officer type. Her older brother had just recently been killed in the war, right? So you’d think she’d be younger. Maybe her character was supposed to be young, but the actress wasn’t. She was born in '65, which is about the youngest I can find out of all the actors.

Well, Ivanova was 28 when the series debuted (if we assume Claudia’s age as Susan’s.) That’s about right for an ambitious Lt. Commander. Garibaldi was 37. Dr. Franklin was 32. Zach Allen was 43, but Jeff has always played younger roles.

OK, I forgot the series debuted in '94. Still, the actors were all “older,” relatively speaking. Not that that’s a bad thing, I think it’s cool. I just wonder why, at a minimum, no one on the show was born before '65.

Someone born in '65 would’ve been 29 in 1994. How many of the characters could’ve been believable if they were under 30? Maybe Zack, but Jeff Conaway was a good choice for him.