As much as I personally love Deep Space Nine, a case can be made that major features of the show were ripped off of Babylon 5. Although the first episode of DS9 hit the airwaves six weeks before the first Babylon 5 television film, it is widely known that Paramount had access to Babylon 5 creator J. Michael Straczynski's show bible for some time. (For further reading on this, see here.)
Apart from the broad similarities, I noticed that the same distinctive style of mug appears in both shows.
Raktajino (Klingon coffee) and its preferred serving mug appear for the first time in the Season 1 DS9 episode "Dax", which aired February 14, 1993. Here is a screenshot from the episode, showing Dr. Bashir with the mug:
Now here is a nearly identical style of mug in Babylon 5, as seen in its Season 1 episode "Eyes":
This episode aired on July 13, 1994. The mugs began appearing in Babylon 5 a few episodes prior to this one, but they still appeared in DS9 more than a year earlier.
Is there a story behind the use of these mugs in Babylon 5? Was this a subtle attempt to draw attention to DS9 having copied crucial elements of Babylon 5 ?
Update: As a commenter and an answerer have pointed out, these mugs have a real-world naval precedent, but consider the following:
- (a) I found it odd that both shows should choose to use that style of mug at the same time, especially as no other spacefaring shows of the time had them;
- (b) in-universe, the Replimats on DS9 almost certainly produced Cardassian-style drink containers, and so out-of-universe the intention was likely to have a foreign-looking mug rather than a mug tied to human naval traditions;
- (c) neither Deep Space Nine nor Babylon 5 is a ship — under routine operations, neither station would expect turbulence or "heavy seas", supported by the fact that we often see glassware in use, especially on Babylon 5.