World's largest acidic geyser erupts in Yellowstone after six-year dormancy

Exam-focused facts from the 5 March 2026 current affairs briefing.

Key facts

Echinus Geyser in Yellowstone National Park's Norris Geyser Basin erupted on 7 February after last erupting in 2020.
The United States Geological Survey (USGS) noted the geyser's eruptions have resumed to 2017-era rates, lasting up to three minutes and reaching water heights of up to 30ft.
Echinus is the world's largest acidic geyser, named for surrounding rocks resembling sea urchins (echinoderms).
Acidic geysers are rare because acidic water can break down rock; Echinus survives as its acidity is low, similar to orange juice or vinegar.