The volcanic eruption in Tonga caused shock waves with a speed of about 1,200 km - theinformant.co.nz

It was not only one of the largest volcanoes, but also the fastest in history:

It was not only one of the largest volcanoes, but also the fastest in history: an eruption. Honga Tonga – Hong HappiOn the island of Tonga, Polynesia, shock waves were recorded with a speed of 1,158 … [+2053 chars]

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