66 million years B.C. - Chicxulub / Yucatan: There was no warning. And unlike today, this planet killer has no fancy scientific name, but was named for the region where it hit: Asteroid Chicxulub. The asteroid burned through the sky at more than 40 times the speed of sound and crashed into the Earth's crust. It produced an explosion equivalent to 100 trillion tons of TNT, about seven billion times more powerful than the Hiroshima bomb.
The plunge into the earth's crust caused shock waves in the form of tsunamis and earthquakes.
Too big to fail?
Quite the opposite. The age of the giant lizards was over.
When the asteroid hit, it vaporized a large portion of the Earth's crust. The debris rose like a fiery cloud above the impact site and made its way through the sky. The cloud spread rapidly until it enveloped the entire earth. Then these clouds rained back into the atmosphere, heating the upper atmosphere so much that planet Earth literally burned.
Over the next few months, the tiny particles trickled back to the ground, covering the entire planet with a layer of asteroid dust. The soot from the fires, combined with the dust from the impact, blocked the sun's rays and plunged Earth into a long, dark winter. The loss of light suppressed photosynthesis and, as a consequence, most food chains collapsed and a mass extinction ensued. Breeding seasons became shorter and conditions much harsher. All living things had been affected in some way, both on land and in the sea.
Life on Earth was in the process of reinventing itself.
Wake up calls
Smaller celestial bodies, aka meteors, that are classified as "potentially dangerous" only hit about every 10,000 years (well thank you very much...). But they would have a 71% probability of crashing into one of the oceans that cover most of the Earth. The people in Tunguska and Chelyabinsk were not so lucky....
What exactly is whizzing past planet Earth or is certain to hit Earth again? Asteroid, meteorite or comet? Well, if such a chunk from space hits your vicinity, the correct designation may not matter to you, but if you want to talk intelligently until then, this overview will help...
Tunguska event (RU - 1908)
The Tunguska event consisted of one or more very large explosions on June 30, 1908 in the Yeniseisk Governorate of Siberia. The most probable cause is considered to be the entry of an asteroid or a small comet into the Earth's atmosphere, where it exploded at an altitude of a few kilometers.
Latest calculations assume an explosive effect comparable to 2 - 5 megatons of TNT. The atomic bomb dropped by the United States on Hiroshima in 1945 had an explosive force of about 13 kilotons of TNT.
Chelyabinsk meteor (RU - 2013)
February 5, 2013, 9:20 a.m. local time - The object came from the direction of the Sun and therefore could not be detected by any of the sky monitoring programs (such as NEAT, LINEAR, LONEOS, CSS, CINEOS, Spacewatch). A TNT equivalent of over 500 kilotons was the most recent warning shot from space. The International Astronomical Union classified the event as a "super bolide."
Live footage of the meteorite impact - 'Little Big Bang'