According to Aatish Bhatia at Nautilus, about 1,988 miles (3,200 km) away from Krakatoa, residents of Western Australia and Papua New Guinea reported hearing a series of loud reports, resembling those of artillery in a north-westerly direction.
Over 2,983 miles (4,800 km) away on the island of Rodrigues in the Indian Ocean, locals reported hearing what sounded to them like the distant roar of heavy gun fire.
This immense sound was caused by a record-breaking volcanic eruption that sent smoke up almost 50 miles (80 km) into the air as ash fell into the ocean some 12.4 miles (20 km) away. Burning hot debris was shot from the mouth of Krakatoa’s volcano at speeds of up to 1,600 mph (2,575 km), which is more than double the speed of sound.
This event has been dubbed the greatest natural disaster of the 19th century, because with such an incredible release of pressure also came severe consequences for the surrounding area.
Shock waves from the volcanic eruption traveled around the world several times, and caused a tsunami over 45 meters high (148 feet) and weighing over 600 tonnes, which ended up hitting the shores of Sumatra and Java, absolutely decimating their coastal regions.
Far away in the waters off South Africa, ships were being rocked by another set of tsunamis. As Bhatia explains at Nautilus, you most certainly wouldn’t have wanted to be on the water less than 60 miles (100 km) away from Krakatoa at the time of the explosion:
“The British ship Norham Castle was 40 miles (64 km) from Krakatoa at the time of the explosion. The ship’s captain wrote in his log, ‘So violent are the explosions that the ear-drums of over half my crew have been shattered. My last thoughts are with my dear wife. I am convinced that the Day of Judgment has come.’”
According to The Independent, the force of the blast was 10,000 times stronger than that of a hydrogen bomb, and Bhatia reports that the sound was registered at around 172 decibels over 100 miles (160 km) away.
This is bonkers, seeing as the human threshold for pain is 130 decibels, and the sound of a jet engine when you’re standing right next to it is 150 decibels. Below is a video shot by a couple in Papua New Guinea that shows a volcano erupting and the shockwave that followed.