Explosions, both natural and man-made, have caused awe and terror for centuries. Here are 10 of the most powerful explosions the world has ever seen, with a surprise honorable mention at the end.
The Halifax Explosion
In 1917, a French cargo ship fully loaded with explosives for World War I accidentally collided with a Belgian vessel in the harbor of Halifax, Canada. It exploded with more force than any man-made explosion before it, equivalent to roughly 3 kilotons of TNT. The blast sent a white plume billowing 20,000 feet (6,100 meters) above the city and provoked a tsunami that washed up as high as 60 feet (18 meters). For nearly 1.2 miles (2 km) surrounding the blast center, there was total devastation, and roughly 2,000 people were killed and 9,000 injured. It remains the world's largest artificial accidental explosion.
Chernobyl
In 1986, a nuclear reactor exploded at Chernobyl in Ukraine, then part of the Soviet Union. It was the worst nuclear accident in history. The blast, which blew the 2,000-ton lid off the reactor, sent out 400 times more radioactive fallout than the Hiroshima bomb, contaminating more than 77,000 square miles (200,000 square km) of Europe. Roughly 600,000 people were exposed to high doses of radiation, and more than 350,000 people had to be evacuated from contaminated areas.
The Trinity Blast
The first atom bomb in history, dubbed "the gadget," was detonated at the Trinity Site near Alamogordo, N.M., in 1945, exploding with a force of roughly 20 kilotons of TNT. Scientist J. Robert Oppenheimer later said that while he watched the test, he thought of a line from the Hindu scripture the Bhagavad Gita: "I am become Death, the destroyer of worlds." Nuclear weapons later ended World War II and ushered in decades of fear of nuclear annihilation. Scientists recently found that civilians in New Mexico may have been exposed to thousands of times the recommended level of public radiation.
Tunguska
The mysterious explosion near the Podkamennaya Tunguska River in 1908 flattened some 500,000 acres (2,000 square kilometers) of Siberian forest, an area nearly the size of Tokyo. Scientists think the blast was caused by a cosmic impact from an asteroid or comet perhaps 65 feet (20 meters) in diameter and 185,000 metric tons in mass -- more than seven times that of the Titanic. The resulting explosion could have been roughly as strong as four megatons of TNT -- 250 times more powerful than the atom bomb dropped on Hiroshima.
Mount Tambora
In 1815, Mount Tambora in Indonesia exploded with the force of roughly 1,000 megatons of TNT, the largest volcanic eruption in recorded history. The blast hurled out roughly 140 billion tons of magma and not only killed more than 71,000 people on the island of Sumbawa and nearby Lombok, but the ash it released created global climate anomalies. The following year, 1816, became known as the Year Without a Summer, with snow falling in June in Albany, N.Y., river ice seen in July in Pennsylvania, and hundreds of thousands of people dying of famine worldwide.
The K-T Extinction Impact Event
The Age of Dinosaurs ended in a cataclysm roughly 65 million years ago that killed off roughly half of all species on the planet. Although research suggests the planet was on the verge of an environmental crisis before the Cretaceous-Tertiary or K-T extinction, the straw that broke the dinosaur's back is widely thought to have been a cosmic impactvast crater roughly 110 miles (180 km) wide at Chicxulub on the coast of Mexico may be the blast site.
The K-T Extinction Impact Event
The Age of Dinosaurs ended in a cataclysm roughly 65 million years ago that killed off roughly half of all species on the planet. Although research suggests the planet was on the verge of an environmental crisis before the Cretaceous-Tertiary or K-T extinction, the straw that broke the dinosaur's back is widely thought to have been a cosmic impactvast crater roughly 110 miles (180 km) wide at Chicxulub on the coast of Mexico may be the blast site.
Comet Shoemaker-Levy 9
The comet Shoemaker-Levy 9 collided spectacularly with Jupiter in 1994. The giant planet's gravitational pull ripped the comet apart into fragments up to 1.8 miles (3 km) wide, and they struck at 37 miles (60 km) per second, resulting in 21 visible impacts. The largest collision created a fireball that rose about 1,800 miles (3,000 km) above the Jovian cloudtops as well as a giant dark spot more than 7,460 miles (12,000 km) across -- about the size of the Earth -- and was estimated to have exploded with the force of 6,000 gigatons of TNT.
Shadow-casting Supernova
Supernovas are exploding stars that often briefly outshine entire galaxies. The brightest recorded supernova in history was sighted in the constellation Lupus (Latin for wolf) in the spring of 1006. The extraordinary golden explosion now known as SN 1006 took place roughly 7,100 light years away in a fairly nearby part of the galaxy, and was bright enough to cast shadows and read by at night, remaining visible for months in the daytime.
The Farthest Recorded Explosion
Gamma ray bursts are the most powerful explosions known in the universe. The light from the most distant gamma ray burst seen yet, dubbed GRB 090423, reached our world even from about 13 billion light-years away this year. That explosion, which lasted just a little more than a second, released roughly 100 times more energy than our sun will release in its entire 10 billion year lifetime. It likely originated from a dying star 30 to 100 times larger than the sun.
Oh, and ...
Honorable Mention: The Big Bang
The universe was born in the Big Bang, theorists say. Although it is often thought of as an explosion -- perhaps because of its very name -- it actually wasn't. In the very beginning, the universe was super-hot and extraordinarily dense. The common misconception is that the universe then exploded out from a single, central point into space. The reality appears to be much stranger -- instead, the fabric of space itself seems to have stretched, and as it expanded it carried galaxies along with it like raisins in a rising loaf of bread.