Warning: frequent observation of geysers over time may become an obsession.
There is no cure, but treatment can consist of regular visits to geysers, or becoming a member of the Geyser Observation and Study Association (GOSA), a citizen-science group of 300 members.
"The variability is what keeps us interested," said Ralph Taylor, president of GOSA and an active volunteer at Yellowstone National Park.
Just as there are wolf watchers, so are there geyser gazers - people who visit Yellowstone regularly for days or weeks at a time, Taylor said. He's been geyser gazing since 1966 and has been a park volunteer for the past 10 years.
Many GOSA members easily have spent more time observing individual or groups of geysers than have the professionals, Taylor said.
Some GOSA members faithfully track individual geysers, he said, while others are more eclectic, traveling all over the park to see the latest phenomena. Other members plan their days around a predictable geyser - like Great Fountain or Beehive - and then look elsewhere, he said.
There's a great deal of geyser gazing gossip (say that fast, three times), where GOSA members exchange the latest news and tips about the ever-changing behavior of Yellowstone's geothermal features.
You can recognize GOSA members, said Taylor, because "they carry FRS [short range two-way] radios to call in and share their observations." They often zip around geyser basins on bicycles, he said, all the better to see anything new or different.
There's a lot to see in Yellowstone Park.
Half of the world's 700 geysers are right here in Yellowstone National Park. There are approximately 10,000 geothermal features in the park - geysers, mudpots, hot springs and fumaroles, or steam vents.
Geyser eruptions can range from a few minutes to days. Some never seem to stop. Others can be dormant for years or decades before erupting with the roar of a jet engine. Some geysers are highly predictable, such as Old Faithful, whose eruptions can be pinned down within 10 minutes by experienced park rangers, 90 percent of the time. Catching other geysers erupt can be a once-in-a-lifetime proposition.
Taylor has been hoping to see the Steamboat Geyser erupt (Norris Geyser Basin) for some 40 years, and hasn't seen it yet. The world's tallest active geyser, Steamboat can erupt to more than 300 feet (90m), showering viewers with its mineral-rich waters. For hours following its rare 3 to 40 minute major eruptions, Steamboat thunders with powerful jets of steam. And full eruptions are entirely unpredictable.
"What's been my best moment? Gee, there have been so many. I guess I'd say it was my first sight of Giant (Upper Basin) in 1997. I literally ran across the parking lot," Taylor said.
Yellowstone's geysers are the complex interaction of precipitation - mostly heavy winter snows - and the heat from within a 35-mile-long magma chamber 10 miles below the surface. Water and heat are brought together by a system of fissures. The result is a sort of magic.
It is very difficult to say what sort of advice Taylor would have for a Yellowstone visitor, on any given day.
"I'd need to know how long they're going to be here, and then gauge how interested they are. I'd have to consider what's happening right then before I made any suggestions," Taylor said.
Old Faithful isn't the largest or most regular geyser, but it erupts more frequently than any other big geysers. The combination of easy access, beauty and predictability make it the most visited geyser in the park.
Most visitors should start at the park's Old Faithful Visitor Center, where they can join a ranger walk and attend a geyser program.
The center will also list the tentative next eruption time for Old Faithful and four other geysers: Castle, Grand, Daisy and Riverside.
The Geyser Observation Study Association was founded in 1983. Its members are known for detailed observations, meticulous records and computer analysis. Its Internet site is www.geyserstudy.org