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On March 22, 1989, the asteroid 4581 Asclepius passed the Earth from a distance of 684,000 km. Although this exceeds the Moon's orbital radius, the close pass received attention at that time, especially since the asteroid passed through the exact position of Earth only six hours earlier. Geophysicists estimate that a collision with Asclepius would have released energy comparable to the explosion of a 600 megaton atomic bomb.
This ATL is one where the asteroid arrived six hours early, crashing into the Earth.
The asteroid that struck the Earth on March 22 wasn't detected by astronomers until it was too late to do anything. It crashed into the North Atlantic Ocean, several dozen miles away from the Eastern Seaboard. Several hours later, a tsunami crashed into the coasts of the Atlantic. New York City was flooded, as were many cities such as Boston and Washington, D.C. There was a global depression that lasted for over a decade.
Soviet Union, collapsed in the late 90's