Later, researchers collected samples of volcanic rock for analysis ... Most of the U.S. volcanoes that scientists consider to be active are found in Hawaii, Alaska and the West Coast. Worldwide, around 585 volcanoes are considered active.

About two months before Mauna Loa spewed rivers of glowing orange molten lava, geologists detected small earthquakes nearby and other warning signs.

About two months before Maunaloa spewed lava, geologists detected small earthquakes nearby and other signals. Now a study of the volcano’s lava confirms that molten rock within Earth's crust was rising upward about 70 days before the eruption in late November 2022.