I had never heard of Prisoners Of Gravity until I saw it mentioned on Facebook. Finding it helps justify time on Facebook somewhat. It's a 1989 Canadian show that aired on TVOntario for 5 seasons. From season 2 on it also appeared on PBS in the US. I checked on YouTube and sure enough someone has about 50 episodes of the 139 that they made. It was co-created by Mark Askwith and Daniel Richler.
It's hosted by Rick Green, he was in The Frantics comedy group, they had a great sketch comedy show called Four On The Floor. Rick played Bill Smith on The Red Green Show, a series he co-created and wrote for the 11 seasons.
Prisoners Of Gravity has Rick escape the Earth and go live in a space station. Each week he talks about SF, in pretty much any format you can find, and some about comic books. He's got interviews with all sorts of creators that were conducted by a team that went to SF conventions. In the few that I sampled I saw Will Eisner, William Gibson, Stan Lee, Neil Gaiman, Bob Kane and Harlan Ellison. I downloaded the lot and will take a look at them in the future.