Huge underwater volcanic blast detected by scientists on other side of world

Image source, Tonga Geological Services

A huge volcanic eruption last year was detected by scientists around 18,000km away on the other side of the world!

The underwater eruption of the Hunga-Tonga Hunga-Ha'apai in the Pacific Ocean on 15 January 2022 sent pressure waves through Earth's atmosphere.

These were then picked up by a collection of seismometers (devices that monitor the earth's movement to detect things like earthquakes) placed by scientists in the Canary Islands.

The project called Upflow was led by scientists from the University College London, and was set up to monitor earthquakes.

But the scientists were blown away by how far their equipment was able to reach, and how it could be used to help in the future.

Video caption, Watch: Satellite images capture the moment the giant underwater volcano erupts in 2022

The Hunga-Tonga eruption in 2022 produced the highest ash cloud ever recorded, sending small bits of rock more than half-way to space!

As well as this, the energy involved also shook the atmosphere, sending out air waves moving at the speed of sound (around 343 metres per second) - called Lamb waves - in all directions.

The blast was one of a number of interesting signals picked up by the Upflow instruments in the Azores-Madeira-Canary Islands region.

Others included a group of whales singing, and a ship carrying very expensive cars exploding and sinking.

Image source, UPFLOW/A.FERREIRA

Image caption, The Upflow ocean-bottom seismometer project is led from University College London, UK

As part of the project, 50 highly sensitive seismometers were placed 5,000m below on the Atlantic Ocean floor for one year, ending in September 2022.

The scientists' goal was to use the signals to help them picture the inside of the planet, investigate the volcanic magma that rises up from deep, and which, when they break through the Earth's crust, become volcanoes.

As part of its year-long mission, the network of devices recorded seismic signals from more than 250 large earthquakes worldwide, including a Magnitude 8.2 in Alaska.

The Upflow team hopes to share more of its research over the next few years.