Morrisons supermarket in Aberystwyth had to close some of its tills, after tremors from a suspected sonic boom caused ceiling tiles to move.
The tills were closed briefly while staff checked for damage.
There have been other reports of rooms shaking, after many people heard what they thought was an explosion in the town.
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The former nurse became an "active cannabis dealer" in the market town of Pwllheli, a court heard.
Welcome to the Newsweek Quiz - where we'll be testing your knowledge from the last seven days of news here in Wales.
As far as today goes, the south is enjoying the best of the sunshine. Always a few showers possible in the north.