I think Netflix is the best. It has a vast collection of science - fiction content. You can find everything from big - budget blockbusters to low - key indie science - fiction gems. There are alien - invasion movies, time - travel series, and stories about post - apocalyptic worlds.
Hulu also offers some good science fiction content. They have shows that are more on the indie or cult side of science fiction. Some of their original series have a unique take on the genre, and they also have a selection of older, cult - classic science - fiction movies that you might not find on other services easily.
It's hard to say exactly. Different streaming services acquire rights at different times. Keep an eye on popular ones like Netflix, Hulu, or Amazon Prime Video.