Small splatters of molten lava have been ejected from Hawaii's Halemaumau Crater for the first time since 1982.
The volcano sits in Hawaii Volcanoes National Park on the Big Island (see map).
Officials with the U.S. Geological Survey's Hawaiian Volcano Observatory say some of the particles—the largest of which measure four inches (ten centimeters) across—have landed on the rim of the crater.
Scientists say the gas from the new vent at Halemaumau is thick with ash, making the plume from the 100-foot-wide (30-meter-wide) vent appear brown.
Officials are continuing to monitor the activity and say aviation agencies have been warned that the ash may threaten aircraft in the area.
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