Can someone help me figure out the source of the noise I’m hearing?

it sounds like a jet airplane. however, it’s been going on for ten minutes. way too long for a plane. also, it sometimes goes away, but then it comes back pretty quickly. Almost as if the source is going back and forth or in a circle. It’s not a motorcycle, and it’s 11:30 pm where I am, so it’s not construction either.
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