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So if it wasn’t aliens, terrorists or Russian hackers, what was it?

On Thursday night, an electrical equipment mishap in Astoria, Queens, turned New York City’s sky into an eerie blue, causing mass bewilderment, rampant speculation and a not insignificant amount of panic.

By Friday morning, it was as if nothing had happened.

The power was back on for those who had lost it. Flights were operating as expected at La Guardia Airport, which was forced to ground all flights after its lights went out. And the No. 7 subway line, which was delayed after the incident, was operating with “good service.”

The sky was back to its appropriate hue.

Still, even if the aqua glow didn’t linger for long, the questions did. Among them: Did the accident leave any pollution or contamination? (Authorities said no.)