I don't think he knew he was going to die two days ago, even if he had he might not have wanted to upset his viewers, he ways always cheerful on his show.
I used to watch his few minute show just before going to bed, just before PBS would go off the air at night. It was like the opposite of an alarm clock: telling me it was OK to go to sleep now and have blissful dreams. I'll be following Cockmaster Flash's lead and I'm glad there was a box of tissues within arms reach when I saw this.
I wanted to make the joke that this episode is about the Triangle of Star Trek References and puts to bed many of the debates about the size of the Federation, but I'm too sad to be a sad nerd right now.
Goddammit
If there is such a thing as a soul, I hope that Jack's has the chance to visit the stars and other galaxies that he taught me to appreciate.
Goodbye Teacher...