I come to SE one evening, and to my vast happiness discover that I have just earned 70 rep points due to 7 upvotes on a single answer.
This causes me to think deeper. No, not about whether it's healthy that earning imaginary internet points offers me such a dopamine hit. About why would I get that rep, suddenly.
You see, this is an old answer that got 7 upvotes. (On a site where 7 upvotes on a brand new, non-HNQ answer, is a healthy amount).
My curiosity is piqued, as to what was the sudden popularity upswing's reason. And I want to investigate.
Usually, when an old post gets many upvotes, it's because they got a bunch more new views for one of three reasons:
Someone edited the question or one of its answers.
That's easiest/fastest to check, and the least likely cause when it's that many upvotes at once.
An alternative is 2 other reasons, both of which can be summed up as "many people found a new reason to visit the post that day".
Some new SE question linked to it (as Related, or closed as dupe of mine).
This can be checked, but not as easily if the question has 10-20 "Related" questions on the site.
Some outside source (either from a different SE, or outside SE) linked to it.
May be i'm not thinking of some other reason?
So, the issue is: #2 is hard and time consuming to check given the tools I'm aware of; and #3, I don't even know how to check.
Intuitively, I assume they can all be checked by finding out the source of recent visits to the question, but I don't have a first clue if that's doable on SE, or how to do it.
Is there a reasonably scalable and efficient way I can find the reason why an old post got suddenly popular within the last day?
 As per Josh Caswell, it was indeed the case of #1 in my specific answer, but let's pretend it wasn't, since I'm asking a generic question and that isn't always the case)