Scientists and villagers sheltering from a pulsing volcano in the central Philippines fear today's full moon could finally spark a violent eruption.
Vulcanologists have warned that Mount Mayon, in the province of Albay, could explode at any time with the gravitational pull of a full moon could provide the final push.
"To put it in a simple way, it's like it massages a volcano," the head of monitoring and eruption prediction at the Philippine Institute of Volcanology and Seismology, Ernesto Corpuz, said.
A full moon coincided with at least three of Mayon's near 50 explosions, including the two most recent in 2000 and 2001, Mr Corpuz said.
Nearly 40,000 people have been evacuated from a 5-mile danger zone on the southeast flank of the volcano, which has been spitting plumes of ash since July.
But some people have yet to leave their livestock and vegetable plots despite an encroaching four-storey-high wall of scalding lava that has streamed more than 4 miles from Mayon's crater.
"I'll leave tonight because of the full moon. My wife and five kids are already gone," said Ambrosio Baranquil, a 41-year-old farmer, whose village is less than two miles from the foot of the mountain.
In schoolhouses, crowded with families who have fled their homes, locals swapped tales of Mayon's previous blasts.
"I've witnessed six eruptions, the first in 1928 and the strongest in 1968 when rocks as big as houses came tumbling down," said Isabel Lodana, an 84-year old grandmother.
The 8,077 foot mountain is the most active volcano in the Philippines and during its most destructive eruption in 1841 buried a town and killed 1,200 people.
President Gloria Macapagal Arroyo has said she is confident there will be no casualties if Mayon blows.
The Philippines, which sits on a seismically active stretch of the Pacific Ocean, known as the "Ring of Fire", is prone to natural disasters such as earthquakes and volcanic eruptions and flooding caused by tropical storms.