The explosion at the mountain summit came shortly after 4am following two weeks of volcanic activity that sent lava flows into neighborhoods and destroyed at least 26 homes.
The eruption probably lasted only a few minutes, and the ash accumulations were minimal, with only trace amounts expected near the volcano, said Mike Poland, a geophysicist with the US Geological Survey.
Some people in the community closest to the volcano slept through the blast, said Kanani Aton, a spokeswoman for Hawaii county civil defense, who spoke to relatives and friends in the town called Volcano.
At least one person who was awake heard nothing. John Tarson, who operates Epic Lava Tours, is an early-riser and said he only learned about the eruption because he received an alert on his phone.
Tarson said the ash plume looked different than others he has witnessed because of its sheer height. A video he shared on Facebook showed a towering column of ash reaching into a hazy sky.
“What I noticed is the plume was just rising straight into the air, and it was not tipping in any direction,” he said.
“We’ve been expecting this, and a lot of people are going to see it and get excited and scared,” he added.
Authorities cautioned that wind could carry the ash as far as Hilo. The National Weather Service issued an ash advisory until noon. Several schools closed because of the risk of elevated levels of sulfur dioxide, a volcanic gas.
Robert Hughes owns the Aloha Junction Bed and Breakfast, about a mile and a half from the crater. He said he did not hear anything either and is in an area that did not get any ash.
So far, he said, Thursday has been a “nice rainy day”.
His business has been hit hard by fears of the volcano, once an attraction for visitors. He said he’s lost hundreds of reservations and had just three guests Thursday instead of the 12 to 14 he has typically served.
One of the guests was a news reporter. The other two were from Italy.
“In the old days, people used to love to come see the volcano. They’d even take their little postcards, burn one corner in the lava flow, mail then off, stuff like that,” he said. “Now they’re acting like it’s all super-dangerous and everything, but it just kind oozes out.”
The crater sits within Hawaii Volcanoes national park, which has been closed since 11 May because of the risk of a more violent eruption.
Officials have said the eruption is not likely to be dangerous as long as people stay out of the closed park.
Kilauea is one of the world’s most active volcanoes. An eruption in 1924 killed one person and sent rocks, ash and dust into the air for 17 days.
Scientists warned on 9 May that a drop in the lava lake at the summit might create conditions for an explosion that could fling ash and refrigerator-sized boulders into the air.
Geologists predicted such a blast would mostly release trapped steam from flash-heated groundwater. Communities a mile or two away could be showered by pea-size fragments or dusted with non-toxic ash, they said.
The volcano has been erupting continuously since 1983. It is one of five volcanoes on Hawaii’s Big Island, and the only one currently erupting.
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