In the mid 1970’s-early 1980’s, WAVE TV 3 NBC in Louisville, KY would air a made for TV movie around 3 or 4pm during the week. I remember seeing all the classics as a child right after school, “Where Have All the People Gone?”, “The Stranger Within”, “Don’t Be Afraid of the Dark” etc. many, many times as they aired some of the better films multiple times a year. One time during “science fiction week”, I remember seeing a film in which a man who appeared to be a scientist (I seem to remember him wearing a white labcoat or something similar), and at least 2 children (possibly an entire ship full of people but I only remember those people in particular) went out in a spaceship to explore or something, and wound up lost in space. At the end of the film they enter a black hole (which at the time was the first I’d ever heard mention of one before), and after passing through they discover they’re close to earth. I’m guessing it was either a pilot film or a made for tv movie as that’s generally what they would show on the daily movie. I consider myself fairly knowledgeable about horror and sci-fi shows and films (my wife and friends would say it borders on obsession), especially the older ones, but this is one I’ve never been able to hunt down.