One way is to search online on websites dedicated to literary agents. For example, AgentQuery.com. Another option is to look at the acknowledgments section in successful science fiction books to see which agents represented those authors. Also, attending science fiction writing conferences can be helpful as agents often participate in such events.
Well, first of all, you should create a list of well - known literary agencies. Then, visit their websites one by one and look for information about their submission guidelines and the genres they are interested in. For instance, some agencies like Writers House or Curtis Brown might have agents who are into science fiction. You can also subscribe to newsletters of writing organizations. They often share news about agents on the lookout for specific genres, including science fiction.
You can start by following industry blogs and forums related to science fiction writing. Some agents may post about their interests there. Additionally, networking with other science fiction writers can be valuable. They might have information about agents who are actively seeking science fiction manuscripts. Don't forget to also check the websites of major publishing houses, as they sometimes list their affiliated agents who could be interested in science fiction.