mystery booms
The following video, produced by the Enigma Seeker Youtube channel, is a compilation of news reports about loud booms heard across the US in 2015. They're often unexplained, or the explanation provided by the authorities falls short of actually explaining the cause of the booms.

Meteor fireball and seismic activity has increased dramatically in recent years, so we suspect a that number of these booms can be attributed to overhead meteor explosions or are earthquake-related.