Wanggongchang Explosion

The Wanggongchang Armory was located about 3 kilometres (1.9 miles) southwest of the Forbidden City, in modern-day central Xicheng District. It was one of the six gunpowder factories administered by the Ministry of Works in the Beijing area, and also one of the main storage facilities of armor, firearms, bows, ammunition, and gunpowder for the Shenjiying defending the capital. It was normally staffed by 70 to 80 personnel.

The most detailed account of the explosion was from a contemporary official gazette named Official Notice of Heavenly Calamity (Chinese: 天變邸抄; pinyin: Tiānbiàn Dĭchāo). The explosion reportedly took place at Sì shi (between 9 and 11 o'clock) on the late morning of May 30, 1626. The sky was clear, but suddenly a loud "roaring" rumble was heard coming from northeast, gradually reaching southwest of the city, followed by dust clouds and shaking of houses. Then a bright streak of flash containing a "great light" followed and a huge bang that "shattered the sky and crumbled the earth" occurred, the sky turned dark, and everything within the 3–4 li (about 2 km or 1.2 miles) vicinity and a 13 square li (about 4 km² or 1.5 mi²) area was utterly obliterated. The streets were unrecognizable, littered with fragmented bodies and showered with falling roof tiles. The force of the explosion was so great that large trees were uprooted and found to be thrown as far as the rural Miyun on the opposite side of the city, and a 5,000-catty (about 3 metric tons) stone lion was thrown over the city wall.[2] The noise of the blast was heard as far as Tongzhou to the east, Hexiwu to the south, and Miyun and Changping to the north, and tremblings were felt over 150 km away in Zunhua, Xuanhua, Tianjin, Datong and Guangling. The ground around the immediate vicinity of Wanggongchang Armory, the epicenter of the explosion, had sunken for over 2 zhangs (about 6.5 m or 21 feet), but there was a notable lack of fire damage. The clouds over the epicenter were also reported to be strange: some looked like messy strands of silk, some were multi-coloured, while some "looked like a black lingzhi", rising into the sky and did not disperse until hours later.

Several government officials in the city were killed, injured or went missing during the explosion, and some were reportedly buried alive in their own homes. The Minister of Works, Dong Kewei (董可威) broke both arms and later had to retire from politics completely. The palaces in the Forbidden City were under renovation at the time, and over 2,000 workers were shaken off the roof and fell to their deaths. The Tianqi Emperor himself was having breakfast in Qianqing Palace when the explosion happened. After the initial quake all the palace servants panicked with fear, so the Emperor started running to the Hall of Union, followed only by a single guard who remained calm but was later killed by a falling tile. The Tianqi Emperor's only remaining heir, the 7-month-old Crown Prince Zhu Cijiong (朱慈炅), died from the shock.[2]

The late Ming Dynasty was already suffering domestic crisis from political corruption, factional conflicts, and repeated natural disasters (proposed to be due to the Little Ice Age by some historians) leading to peasant riots and rebellions. However, the horror of the Wanggongchang Explosion dwarfed all of those, and the imperial courts criticized the Tianqi Emperor and believed that the incident was a punishment from Heaven as a warning to correct the sins of the emperor's personal incompetence. Tianqi Emperor was forced to publicly announce a repenting edict, and issued 20,000 taels of gold for the rescue and relief effort.

The Wanggong Armory Explosion can be considered a pivotal event in the early modern Chinese history, for multiple reasons. The destruction of the Wanggong Armory, one of the largest stockpiles and manufacturing facilities of firearm and ammunition, resulted in a hardware loss that the Ming military never recovered from. The gold issued for the relief effort put further strain on the Ming government budget, which was already suffering from ever increasing military expenditures in Manchuria against the Jurchen rebellion by Nurhaci, as well as rampant tax resistance by the upper middle class in the more affluent South. The superstitious belief that the incident was a heavenly punishment for the personal failing of the Tianqi Emperor (who was more interested in carpentry than ruling the country) also further eroded the authority and public respect towards the Ming monarchy.

Furthermore, the Wanggongchang Explosion resulted in the death of the Tianqi Emperor's only surviving son, Crown Prince Zhu Cijiong, leaving him heirless. Tianqi himself would die the following year, and his overambitious younger half-brother Prince Zhu Youjian inherited the throne as the Chongzhen Emperor. Chongzhen, who hated the powerful chief eunuch Wei Zhongxian intensely, soon purged Wei,[3] which ironically removed a stabilizing factor within the Ming court. The factional infighting between the resurgent Donglin faction (who were previously persecuted brutally by Wei) and their various political opponents would then intensify during Chongzhen's reign, coupling with Chongzhen's own impatience and rash decisions, would further accelerate the decline and eventual fall of the Ming dynasty 18 years later.

The cause of the explosion has never been conclusively determined. Although there are multiple sources of detailed historical records, the incident happened well before the proliferation of modern science in China, and contemporary interpretations are compounded with superstitious speculations. There were also suspicions that the official account might have been exaggerated with tints of yellow journalism. Throughout the ages, various theories have been put forth, including gunpowder explosion, meteorite air burst, natural gas explosion and volcanic eruption,[2] Despite some hypotheses being regarded as scientifically plausible, no academic consensus has been reached.

Bolide

The smoke trail of the 2013 Chelyabinsk meteor, whose bulbous portion resembles the cap portion of a mushroom cloud but the trail leads sideways instead of downwards.

The bolide hypothesis argues that the description and magnitude of the explosion is more consistent with a meteor exploding mid-air at low/medium altitude while entering the Earth's atmosphere, and that such an air burst may or may not have caused the Wanggongchang Armory's stored gunpowder to explode secondarily.

The descriptions of a preceding flash, roaring sound and rumbling, and showering of rocks and grains of metal, bear resemblance to modern records of exploding bolides (such as the well witnessed 2013 Chelyabinsk meteor). Description of the blast aftermath can also find some resemblance to Leonid Kulik's finding of the air burst obliteration of Siberian forests by the Tunguska event three centuries later. However, no evidence of a classic meteorite strike impact crater has been found, and the description of an alleged mushroom cloud suggests another cause for the explosion. Coincidentally, the Tunguska event, which was a 10–30 megaton airburst (more than 1,000 times more powerful than the Hiroshima bomb) in the upper middle troposphere (at 5–10 km above the surface) that also didn't leave any impact craters.

Another notable issue is the "mushroom cloud" witnessed after the explosion was actually specifically described in historical records as resembling a Chinese lingzhi (Ganoderma lucidum), which is usually more fan-shaped like an upward-facing shower head rather than the more umbrella-like shape of a typical mushroom, suggesting an explosion likely occurring mid-flight rather than arising from the ground. The description of other multi-colored, "messy silk" type clouds also have resemblance to the smoke trails of exploding mid-air bolides witnessed in modern times.

If the bolide hypothesis were ever proven to be true, the Wanggongchang Explosion would be the most lethal impact event in recorded history (surpassing the 1490 Ch'ing-yang event).

• Largest artificial non-nuclear explosions