There's a few options available to you
You can sort questions by newness. Presumably it's one of the questions asked yesterday
You could use the search facility to search for the title.
You could search for it by tag (our questions are usually very well curated).
If you remember the username you used before, you can search by username
If you've got enough rep (20 points) you could ask in the chatroom
For the record, I'm pretty sure this is your question.
Earth sends fleet to destroy an alien species that requires a virus to reach maturity
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