Catabole

This article is about the 1348 asteroid impact event. For the time period of subsequent global effects, see Catabolic Crisis.

Catabole

The Catabolic Destruction of X (1849) by Archibald Glover, oil on canvas
Date	13 September 1348 (1348-09-13)
Time	Unknown, likely 14:15–14:45
Location	17 km (10 mi) off the coastline of X, Cassany (Strait of X, X Sea)
Cause	Impact event of a small asteroid
Outcome	Widespread cataclysmic damage in Calesia, eastern Abaria and northern Hylasia, reduced global temperatures leading to famine (Catabolic Crisis)
Deaths	2.65–3.5 million from direct impact effects; hundreds of millions due to post-impact global famine and epidemic diseases

The Catabole, also referred to as the Catabolic Event or the Great Calamity, was the impact of a superbolide in the Endotheric Sea in the early afternoon of 13 September 1348. The presumably 350–370 m (1,210 ft) diameter, 61 million tonnes heavy near-Earth C-type asteroid with a carbonaceous crondite-like composition, called the Catabolic impactor, struck Earth approximately 17.4 km (10.8 mi) off the shoreline of X in the Strait of X at a shallow atmospheric entry angle of 21.1 degrees and a speed relative to Earth of 28.6 km per second (17.8 mi per second). The impact had profound effects on the course of world history.

The object impacted the sedimentary rock of the sea floor with a kinetic energy equivalent of about 1,150 megatons of TNT and instantaneously formed an impact crater 4.9 km (3.0 mi) wide and 850 m (2,789 ft) deep. The resulting emission of thermal radiation, shock waves, seismic activity, and expulsion of megatsunamis over 80 m (262 ft) tall led to the widespread devastation of communities along the surrounding coasts of the Endotheric Sea and the broader region, killing approximately 2.65–3.5 million people in one of the deadliest single natural disasters in recorded history; numerous major cities such as X and Tornium were entirely annihilated. It was the worst natural disaster in Calesian and Hylasian history, the worst natural disaster in a millenium, and the largest impact event ever witnessed by humankind.

Sulfur-rich gypsum from the seabed was vaporized in large quantities and injected into the atmosphere as aerosols, triggering significant climate change in an impact winter. As a result, extreme weather and harvest failures led to widespread famine, economic distress, the outbreak of epidemic diseases such as cholera and the bubonic plague, and ultimately major religious, political, and social upheaval around the world. It is estimated that about 30% to 60% of Calesia's population, and about 35% of the entire world population, were wiped out during the 1348–1353 Catabolic Crisis in the aftermath.

Events

Discovery and observation

Waldish Emperor Ragnvaldr IV standing before Alsvik and pointing at "a new star" (decorative art from the 1348 Alsivicium)

The observation and study of comets and other star-like objects that appeared temporarily in the night sky, often referred to as "guest stars", was a common practice by the time of the 14th century, particularly because of the notion that they represented omens.

Some of the contemporary Calesian accounts of the discovery of the Catabolic impactor are well preserved. The oldest and most detailed account is that of Dahemian astronomer Julius vom Halderbruck from July of 1340, who described it as a "swiftly moving but pale yellow dot trailing behind Maciune". By that time, the asteroid came within less than 0.01 astronomical units from Earth, allowing for adequate resolution by the naked human eye. It is generally believed that this close fly-by perturbed its solar orbit so that its passing through a gravitational keyhole made impact 8 years later inevitable.

Beginning in August of 1348, astronomers took notice of the asteroid once more, though no recovered account purported that these two sightings were related in any way. Fallish astronomer Presley Combse described it as "ever-growing in illuminating intensity", about the size of the planet Atiner, and a quarter the brightness of the star Vega; the impactor's apparent magnitude was about 3.1. Hyacinthean mathematician Nicodème d'Abraham is credited with first noticing the peculiar behavior of the object's movement across the sky and formulating the idea that "perhaps [it may] touch the earth with extraordinary speed and fiery power if [its] heavenly path is maintained."

Similar and other accounts exist from scholars in Waldrich, the Hon Dynasty, Razan, and Muharanta.

Particularly because of the comparatively unimpressive appearance of the object in the months and days before the impact, interest in its study remained confined to a minor number of astronomers. It is debated whether royal court astronomer Jacobus Bolemer took notice of the sighting alongside vom Halderbruck in 1340 and reported it to Waldish Emperor Ragnvaldr IV, or whether his account of the observation of SN 1330 has been falsely interpreted.

Impact and immediate effects

Copper engraving from 1698 depicting Tornium in flames and destroyed by a tsunami minutes after the impact

Few who were able to witness the actual atmospheric entry of the asteroid survived the impact. Multiple of the sparse eyewitness testimonies remaining described "the sky being split apart by... fire [that] appeared high and wide," followed by "tromendous roars" while the asteroid traversed the atmosphere for no more than five seconds. Based on available information, historians believe the impact to have occured between 14:15–14:45 (2:15–2:45 pm) local time on 13 September 1348.

The object impacted the planet with a relative velocity of 28.6 km per second (17.8 mi per second) and an kinetic energy equivalent of about 1,150 megatons of TNT. The site of contact is located approximately 17.4 km (10.8 mi) off the shoreline of X in Cassany, near X. Almost instantaneously, a crater 4.9 km (3.0 mi) wide and 850 m (2,789 ft) deep was excavated and a fireball of superheated plasma vaporized anything less than 150 kilometers (93 miles) away. Eyewitnesses more than 700 kilometers (435 miles) away reported the spontaneous combustion of any flammable material in sight of the asteroid impact, caused by the released pulse of thermal radiation; the ensuing firestorms easily set ablaze the timber architecture of Calesian medieval towns. Thousands of people in various towns asphyxiated to death within minutes by the fires' rapid consumption of oxygen. Simultaneously, the impact expelled shock wave winds in excess of 1,200 kilometers per hour (750 miles per hour), destroying any man-made structure as far away as X and X (about 250 kilometers (155 miles) from impact) and being heard as far away as 5,000 kilometers (3,100 miles).

Maximum tsunami heights triggered by the Catabole impact

The resulting exertion force as well as ocean water expansion after the crater was refilled led to the formation of megatsunamis over 80 meters (262 feet) tall. The average heights of the waves upon contact with the coasts was about 15 meters (49 feet), allowing for floods to reach deep into the X and the X. The cities that were most severly affected by flooding were X and Tornium, the latter described to "[have] been fully swept away in a monstrous deluge beyond compare." The impact also triggered an earthquake possibly exceeding a moment magnitude of 10 M_W, making it the single strongest seismic event in recorded history. Shocks from the quake were felt throughout Calesia as far as Waldrich and in North Hylasia, and according to some contemporary sources, even Yingok and Dvarika.

An estimated 130 billion metric tons of hot dust, vaporized ejecta, and steam was lifted off the ground and ejected into the higher atmosphere, and in some cases, into space. Considerable ashfall was reported across the entire Endotheric, accumulating to more than 50 centimeters in thickness within the first five hours as far away as Shaghirsenir (2,400 kilometers; 1,490 miles) and Elarai (3,100 kilometers; 1,930 miles). While much of that included meterial that worsened the raging fires in the Endotheric region by heating itself upon re-entry, the impact location in the shallow waters of the Strait of X allowed for vast quantities of sulfur-rich gypsum to be vaporized as well. That vapor and dust was dispersed across the Northern Hemisphere within a day after the impact by high-altitude polar jet streams.

See also

• Catabolic Crisis