(NEXSTAR) — There have long been questions about when Yellowstone’s volcanic system could see an eruption, especially after a massive hydrothermal explosion was caught on camera last summer.

A surprise eruption that shot steam, water and dark-colored rock and dirt dozens of feet into the sky Tuesday sent people running for safety in Yellowstone National Park. The hydrothermal explosion ...

Yellowstone National Park sits atop one of the most studied volcanic systems on Earth, and the question of what a full-scale caldera-forming eruption would do to the United States draws enormous ...