Adding to my point about the three broad streams of science fiction, I would like to suggest that there is arguably a fourth, although I would tend to think of it as a substream of the second. Namely, scientific discovery and technological progress tend, by their very natures, to overturn our view of the world as it is understood to exist; any voyage into unknown or unfamiliar territories has the potential to be terrifying, and stories of this (sub)stream focus upon the inherently frightening aspect (to the point that they are often mistaken for straightup horror stories); it takes, as it’s champion, Mary Shelley, whose Frankenstein was an early meditation upon fears of science killing and replacing God.
The works of HP Lovecraft are based heavily on this stream; on television, it’s represented by shows like the Outer Limits*, and on film by movies like Event Horizon and the Alien series. Interestingly, it seems to interplay very little with streams one and three, largely (I suspect) because campy adventure stories tend to run contrary to any feeling of fear, and detailed scientific explanations automatically make the phenomena they describe less scary.
It is perhaps notable that this (sub)stream is older than the others; I suspect that this may be a reflection of fear being the first, instinctual reaction to the unknown.
* I would say The X-Files, but honestly, I don’t really count it as being SF so much as a type of urban fantasy.