At www.skyandtelescope.com/astronomy-news/close-stellar-encounters-surge/#…. … close stellar encounters. An analysis of our stellar neighbourhood is said to reveal more stellar traffic then recognised – stars that sideswipe our solar system. That potentially hurl hailstorms of comets inward and showering our planet with debris. Not just worlds in collision but stars and solar systems in collision.
Howeer, NASA released a news bite on a small asteroid (boulder sized) that blew apart over Botswana on June 2nd (2018). It was around 6 feet across and was unnoticed until it was a moon distance away. Too late for Hollywood to come to the rescue. See the vieo at www.youtube.com/watch?v=mBvSNYy-EY
The same story is at http://spaceweather.com (4th June 2018). It entered the atmosphere at around 38.000mph and a video taken in South Africa recorded the explosion and burst of light. It sent out waves of low frequency sound (known as infrasound) rippling through the atmosphere.