By NASA/JPL-Caltech – <a rel=”nofollow” class=”external free” href=”https://www.jpl.nasa.gov/images/asteroid/20180723/main-animation-16.gif”>https://www.jpl.nasa.gov/images/asteroid/20180723/main-animation-16.gif</a>, Public Domain, Link
The Tunguska event was an approximately 12-megaton explosion that occurred in Russia. The explosion over the sparsely populated Eastern Siberian FLATTENED an estimated 80 million trees over an area of 830 sq mi of forest. The explosion is generally attributed to a meteor air burst: the atmospheric explosion of a stony asteroid about 160 to 200 feet in size. The asteroid approached from the east-southeast, and likely with a relatively high speed of about 60,000 mph. It is classified as an impact event, even though no impact crater has been found; the object is thought to have disintegrated at an altitude of 3 to 6 miles rather than having hit the surface of the Earth.
The Tunguska event is the largest impact event on Earth in recorded history, though much larger impacts have occurred in prehistoric times. An explosion of this magnitude would be capable of destroying a large metropolitan area. Also inspired real-world discussion of asteroid impact avoidance.