--- title: Yellowstone National Park Hot Spring Death Explained description: The death of a man who ventured into an out-of-bounds hot spring in Yellowstone has alarmed people across internet—here's how it happened canonical: https://time.com/4575511/yellowstone-hot-spring-science/ author: Justin Worland article:opinion: false article:content_tier: free article:published_time: 2016-11-17T22:42:49.000Z article:modified_time: 2026-02-23T01:53:56.704Z article:section: Science og:title: A Man Dissolved in an Acidic Hot Pool at Yellowstone. Here’s Why the Water Is So Dangerous og:description: A man died after trying to bathe in a hot spring og:url: https://time.com/4575511/yellowstone-hot-spring-science/ og:site_name: TIME og:image: https://static.time.com/v3/assets/bltea6093859af6183b/bltda69bad418c6db0d/6988aef6cd1bba001270324a/yellowstone-hot-spring1.jpg?branch=production&width=3840&quality=75&auto=webp&crop=16:9 og:image:width: 1200 og:image:height: 675 og:image:alt: yellowstone hot spring og:type: article twitter:card: summary_large_image twitter:title: A Man Dissolved in an Acidic Hot Pool at Yellowstone. Here’s Why the Water Is So Dangerous twitter:description: A man died after trying to bathe in a hot spring twitter:image: https://static.time.com/v3/assets/bltea6093859af6183b/bltda69bad418c6db0d/6988aef6cd1bba001270324a/yellowstone-hot-spring1.jpg?branch=production&width=3840&quality=75&auto=webp&crop=16:9 ---  # A Man Dissolved in an Acidic Hot Pool at Yellowstone. Here’s Why the Water Is So Dangerous  by [Justin Worland](https://time.com/author/justin-worland/)  ## Justin Worland Senior Correspondent Nov 17, 2016 10:42 PM UTC  A skier viewing Grotto Geyser from the boardwalk, Yellowstone National Park, Wyoming, Dec., 2015\. Image courtesy/Yellowstone National Park. A skier viewing Grotto Geyser from the boardwalk, Yellowstone National Park, Wyoming, Dec., 2015\. Image courtesy/Yellowstone National Park.Neal Herbert—Smith Collection/Gado—Getty Images  by [Justin Worland](https://time.com/author/justin-worland/)  ## Justin Worland Senior Correspondent Nov 17, 2016 10:42 PM UTC The tragic [death](http://time.com/4574226/man-dissolved-yellowstone-park/?iid=sr-link1) of a man who ventured into an out-of-bounds hot spring in Yellowstone National Park may sound shocking, but there’s a reason why the water was so dangerous. As surprising as it might be to learn that a human being dissolved completely in water, the scientific reason why some hot spring water is dangerously acidic and other water completely harmless is completely clear. Scientists behind a 2012 [study](http://onlinelibrary.wiley.com/doi/10.1029/2011GC003835/full) published in the journal _Geochemistry, Geophysics, Geosystems_ laid out the distinction between acidic and harmless water after evaluating water that originated in the Heart Lake Geyser Basin. Safe and unsafe water for humans originates in the same place deep underground, but separates as it comes to the surface. Some water becomes highly acidic as small microorganisms that live in extreme heat break off pieces of surrounding rocks adding sulfuric acid to the water. When that highly-acidic water bubbles to the surface—through mud pots and fumaroles—it is no longer safe for humans. Anyone questioning the safety of water at or near a hot spring should look stay on the path and respect boundaries set by the National Park Service. ```json [{"@context":"https://schema.org","@type":"NewsArticle","@id":"https://time.com/4575511/yellowstone-hot-spring-science/","mainEntityOfPage":{"@type":"WebPage","@id":"https://time.com/4575511/yellowstone-hot-spring-science/"},"headline":"A Man Dissolved in an Acidic Hot Pool at Yellowstone. Here’s Why the Water Is So Dangerous","datePublished":"2016-11-17T22:42:49.000Z","dateModified":"2026-02-23T01:53:56.704Z","description":"A man died after trying to bathe in a hot spring","url":"https://time.com/4575511/yellowstone-hot-spring-science/","keywords":["nature"],"thumbnailUrl":"https://static.time.com/v3/assets/bltea6093859af6183b/bltda69bad418c6db0d/6988aef6cd1bba001270324a/yellowstone-hot-spring1.jpg?branch=production&width=1200&quality=75&auto=webp&crop=1200:675&height=675","author":[{"@type":"Person","name":"Justin Worland","jobTitle":"Senior Correspondent","url":"https://time.com/author/justin-worland/"}],"articleSection":"Science","image":[{"@type":"ImageObject","url":"https://static.time.com/v3/assets/bltea6093859af6183b/bltda69bad418c6db0d/6988aef6cd1bba001270324a/yellowstone-hot-spring1.jpg?branch=production&width=1200&quality=75&auto=webp&crop=1200:675&height=675","width":1200,"height":675,"headline":"yellowstone hot spring","caption":"yellowstone hot spring","creditText":"Neal Herbert—Smith Collection/Gado—Getty Images","representativeOfPage":true}],"publisher":{"@type":"Organization","name":"Time","url":"https://time.com/","logo":{"@type":"ImageObject","url":"https://time.com/images/logo.png","width":528,"height":156},"foundingDate":"March 3, 1923","sameAs":["https://www.facebook.com/time","https://www.instagram.com/time/?hl=en","https://twitter.com/time","https://www.pinterest.com/timemagazine"]}},{"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"item":{"@id":"/section/science/","name":"Science"}},{"@type":"ListItem","position":2,"item":{"@id":"/tag/nature/","name":"nature"}},{"@type":"ListItem","position":3,"item":{"@id":"https://time.com/4575511/yellowstone-hot-spring-science/","name":"A Man Dissolved in an Acidic Hot Pool at Yellowstone. Here’s Why the Water Is So Dangerous"}}]}] ```