One of my favorite short stories of all time is "Nightfall" by Isaac Asimov written in 1941. If you haven't read that one yet, take a look. It was later adopted into a full-length novel by Robert Silverberg.
Much thanks to dear friend Ian Randal Strock for helping me build this list of current short story venues for science fiction authors. Here are my notes!
One of the true classics. Analog wants stories where the scifi aspect is critical - not just a story that happens to be set in the future. They pay 8-10 cents a word for works up to 20,000 words. They want first rights (i.e. unpublished elsewhere before this point). It takes them 2-3 months to get back to you.
Asimov's Science Fiction
Another classic magazine. In this case they pay 8-10 cents per word for up to 7,500 words and then 8 cents per word over 7,500 words. Their range of length goes from 1,000 to 20,000 words. Again they want first rights and they don't allow simultaneous submissions. If you submit here you shouldn't be submitting anywhere else until they give you a response. They want character-based scifi and they do sometimes veer into fantasy but not sword-and-sworcery type. It takes them about five weeks to reply.
Fantasy and Science Fiction
This one is, as you might imagine, a blend of the two genres. This is where one of my favorites, "Flowers for Algernon", got its start. They publish up through 25,000 words. Payment is 7-12 cents per word. They only want one story at a time and there's a 15-day waiting period before you can submit a new one. It can take up to eight weeks to hear back. It must be a first-run work and they don't allow simultaneous submissions.
Nature's Science Fiction section
Nature is a well respected magazine on the general topic of nature. They have a section of their magazine that runs interesting science fiction that relates to their theme. They like shorter pieces - from 850 to 950 words - and it needs to be more of the 'scentific' type of scifi vs generic fantasy. It's good to read their previous issues to see what they tend to run. They don't document what (or if) they pay or their response cycle.
An online-only magazine with some impressive writers. They have a specific length range of 1,000 to 16,000 words. They pay 10 cents per word up to 5000 and then 8 cents per word above that. They need first rights. Their magazines are also audio so the story needs to be able to be read aloud easily. Bonus - they usually respond within a few days!! No simultaneous submissions and wait 7 days before submitting a next story. I love their list of "what we are tired of seeing" (my words) :).
Fantastic Stories of the Imagination
A good spot to try with more esoteric stories. These guys are interesting because they DO take reprints. For first-run stories they should be up to 3,000 words, so fairly short. They love diverse characters. For first-run stories they pay 15 cents per word and for reprints it's a penny per word. They aim to respond within eight weeks. There are no simultaneous submissions. They allow you to submit up to two stories at a time.
This one comes out six times a year. They are currently invitation only, so this is one to put on your radar and keep submitting elsewhere to build up your reputation.
This one is a little tricky - they open and close their submissions for a certain period of time. So you can't just submit when you're ready - you have to watch for the next cycle opening and then submit within that timeframe. They take stories 1,500 to 10,000 words with a preference to those under 5,000. Payment is 8 cents/word for first rights and 2 cents/word for reprints. When they're accepting they typically respond within two days. They don't allow simultaneous submissions nor multiple submissions.
Let me know if you know of any other short story markets for science fiction!
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