Several years ago, I went to a scifi convention in Pensacola and met a man that was selling two of a three volume set of LDS scifi short stories. He told me that the LDS church frowned on scifi and that these had been banned in Utah. I only chuckled to myself and replied that since I was LDS and into scifi maybe I had better look into the situation.
For fun I bought the books. They are terrific. One story is about a guy building a time machine so he can "peek" in on Joseph Smith's first uttered prayer and how the machine could never get it right so in the end he realized God was keeping that sacred.
One of the stories was about Cain and how he traveled the earth begging someone to kill him because he couldn't handle being alive. And of course God had promised him he would never be killed. Intriguing prospect to say the least.
The one that struck me the most was a "futuristic" theme wherein the last of the last days was upon us and the main characters were trying to travel to New Jerusalem for safety. They kept running into people who were evil but wise enough to know these travelers were going to a safe place. One of the bad guys or in this case girl had been an animal lover in the sense that she preferred animals over people. A sort of PETA and abortion activist.
Needless to say all the stories were well written, provoked interesting ideas and stayed fairly true to gospel principles. I suspect my "friend" at the scifi convention was lying about them being banned. Over the years, more church members have embraced and written for scifi (which is different from fantasy). To my knowledge few of them have breached church standards.
I enjoy speculation but recognize it as speculation only. "The Knowing" offers up a fascinating prospect for the last of the last days. While I thought the "seeding" of other earths in the very last scene was too corny, I did marvel how close they came to getting it right. I mean after all who knows but that the lost 10 tribes might come hurdling out of the "north country" which turns out to be space. Battlestar Galactica and all.
In short, scifi has a rich home in LDS legend and doctrine and I for one am glad.