There is a giant volcano in the western United States. It is deep underground. The volcano is so big that scientists call it a "supervolcano." The supervolcano lies beneath Yellowstone National Park in Wyoming.

Scientists have been watching the volcano since 1923. Lately, it has been more active than usual. Some experts wonder if it may erupt soon.

Still, most scientists say there's no need to worry. The Yellowstone volcano is currently dormant. This means it is mostly quiet now.

Scorched Earth

The Yellowstone volcano hasn't always been so quiet. It has had three giant eruptions in the past. These eruptions happened about 600,000 to 800,000 years apart.

The last eruption happened 640,000 years ago. The blast shot ash and gas into the air. The ash was so thick that it blocked out the sun. The inside of the volcano was hot and melted rock into magma. The magma rose out of the volcano and burned the land.

Hopefully Just Some Minor Activity

The United States Geological Survey (USGS) is a government science group. USGS scientists study Earth. They are volcano experts. The USGS agrees that a big eruption is very unlikely.

Instead, they think the volcano may cause smaller events. It could heat water underground. Steam or hot water might shoot from the earth. Slow-moving rivers of lava might ooze from the volcano. These will eventually harden into rock.

For now, the Yellowstone volcano is mostly quiet. Scientists are keeping an eye on it. No one knows how much damage it would cause if it erupts. But most scientists say that's still a long way off.