At 7:17 in the morning on June 30th, 1908, a huge explosion occurred several miles in the air above the Tunguska region of Siberia, with the force of a large nuclear blast. It was probably a small asteroid or comet. The extreme heat generated by the object entering our atmosphere caused it to violently disintegrate before hitting the ground. Witnesses hundreds of miles away reported that it was brighter than the Sun. Even at that distance, the shockwave knocked people down, ruining their breakfast. The explosion destroyed 60 million trees.
Nineteen years elapsed before Russian scientists got around to investigating the site of the impact. This was partially due to the extreme remoteness of Siberia, but also because of a long term, highly coordinated mass procrastination experiment that was already in progress.
The scientists persuaded the government to fund the expedition, based on the assumption that iron from the meteorite could be retrieved and used by Soviet industry. Because the explosion occurred in mid air, no meteorite was found, but the scientists were able to bring back large quantities of fresh Tunguska, which is quite delicious on toast.
Although impact events like these are statistically quite improbable, there is nevertheless a small possibility that at any moment, without warning, the city that you live in could be completely wiped out by a big rock from space.
Sleep well, my friend.