10-15 km Asteroid Wiped Out 75% of Species, Releasing 3 × 10^23 J
Updated
Updated · spacedaily.com · Jun 21
10-15 km Asteroid Wiped Out 75% of Species, Releasing 3 × 10^23 J
1 articles · Updated · spacedaily.com · Jun 21
Summary
A 10-15 km asteroid that hit the Yucatán 66 million years ago triggered the extinction of about 75% of species, with impact energy estimated at 3 × 10^23 joules—roughly 5 billion Hiroshima-sized bombs.
Within seconds, the strike gouged a hole more than 20 km deep and blasted several thousand gigatonnes of rock and asteroid material above the atmosphere, spreading dust, soot and sulfate aerosols worldwide within hours.
That global debris cloud blocked sunlight and drove an impact winter that likely collapsed food webs, though researchers still dispute whether soot or sulfur dominated the cooling and whether the darkness lasted months or more than a decade.
Survival was highly uneven: only about 12% of land-dwelling forms endured, while roughly 90% of freshwater species survived, likely because detritus-based ecosystems were less dependent on living plants and plankton.
The Chicxulub crater—about 180 km wide—was identified in the late 1970s and tied to the extinction around 1990; 2016 drilling later confirmed key details of the impact structure and ejecta.
Would dinosaurs still be alive if the killer asteroid had hit a different location?
How did the impact that erased life also create a long-lasting habitat for it?
Does the key to finding life on Mars lie buried inside its ancient craters?
The Chicxulub Impact: How a 10-Kilometer Asteroid Reshaped Life and Drives Today’s Planetary Defense
Overview
Earth is under a constant, though rare, threat from asteroid impacts. Scientists agree that a devastating strike is certain to happen in the future. Near-Earth Asteroids (NEAs) travel in orbits that can bring them close to our planet, but detecting smaller asteroids—those tens to hundreds of meters wide—is still a major challenge because they are too dim and small for most telescopes. The 2013 Chelyabinsk event in Russia showed the danger: a 20-meter asteroid exploded in the atmosphere, releasing energy equal to 500 kilotons of TNT. This highlights the importance of improving detection and planetary defense.