A new thermal steam vent is grabbing attention in ever-changing Yellowstone National Park

YELLOWSTONE NATIONAL PARK, Wyo. (AP) — A new thermal vent spewing steam in the air at Yellowstone National Park is gaining attention, mainly because it's visible from a road rather than any significant change in the park famous for its thousands of geysers, hot springs and bubbling mud pots.

When Yellowstone's roads open to car traffic in April, tourists will be able to view the new steam column from a pullout as long as the vent remains active. It's located in an area about a mile (1.6 kilometers) north of the Norris Geyser Basin.

The thermal feature was first spotted by scientists last summer and inspired them to trudge across a marsh and measure 171-degree (77-degree Celsius) steam venting from the base of a wooded hill. A thin coat of gray mud confirmed the vent was new, according to a recent online post by scientists with the Yellowstone Volcano Observatory overseen by the U.S. Geological Survey.

Mike Poland, scientist in charge of the observatory, said Monday that such features are often forming and constantly changing in Yellowstone.

“The feature itself is new. That there would be a new feature is, you know, mundane,” he said. “The noteworthy part ... was just that it was so noticeable. But the sort of overall idea that there would be a new feature that formed is pretty normal.”

The new steam plume is located within a 200-foot (60-meter) area of warm ground and appears to be related to hot water that surfaced as a new feature 700 feet (215 meters) away in 2003.

The plume diminished over the winter. Whether it will remain visible from afar this summer, or be stifled by water in the vent, remains to be seen, geologists say.

Still, geological changes in Yellowstone draw interest because the park overlies a volcano that was responsible for powerful eruptions in the distant past. The volcano has had no lava eruption for 70,000 years and no major eruption for 631,000 years, however.

The volcano's magma chamber between 5 and 10 miles (8 and 16 kilometers) under the surface heats the underground water that bubbles up as the park's famous hydrothermal features. Only between 10% and 30% of the chamber currently holds liquid magma.

Despite Yellowstone's sometimes dramatic geological events — including a hydrothermal explosion that hurled hot water and rocks and sent tourists running last summer — geologists emphasize there is no sign the volcano will erupt again any time soon.

Yellowstone’s thermal features come and go, but the park’s most famous one, Old Faithful Geyser, is still going strong.

“There’s so many thermal features. Not only do they come and go, but they change,” Poland said.