Babylon 5: Thirdspace (1998)

An ancient, mysterious artefact is discovered by some of the B5 crew while on a mission. They capture it and and moor it outside the station. The scientists know just as well as the rest of us that mysterious alien artefacts are always trouble, but they want to open it anyhow, and consequences be damned.
It’s debatable about where Thirdspace fits into series continuity, but we’re given some clues. It's set in the middle of the year 2261, so it’s definitely after the end of the Shadow War but prior the problems the B5 crew would have with Earthforce while President Clark was in power. That means it's sometime during the first half of Season 4. The opening narration will contain spoilers if you watch it before having made it at least that far into Season 4.

3 bozo rays out of 5