Bill Nye -- Defends 'Star Trek' Buddy in Bizarre, Unprompted Rant

No one asked Bill Nye about his "Star Trek" pal's messy divorce ... or about Nye's ongoing battle with his former fiancée -- but the Science Guy couldn't wait to tell us all about it.

You'll recall ... Nye ended up in the middle of "Star Trek Voyager" star Robert Picardo's divorce -- because Picardo's estranged wife Linda claimed he and Nye were having an affair.

Nye himself has been fighting with his former flame, Blair Tindall, over $57,000 she owes him stemming from their split in 2006.

Well, according to Nye ... there's been a major development in this war of exes.