Mount Sinabung

For a very, very long time, Sinabung was quiet.

In 2010 it puffed out ash. In 2013 it woke up again and stayed busy for years.

NASA says Sinabung had no confirmed eruptions in the historical record before 2010. The US Geological Survey reports that a small eruption on 28 August 2010 was its first in about 1,200 years. Steam and gas kept rising for almost three years.

A new eruption began on 15 September 2013. Lava piled up at the top into lava domes. When parts of a dome broke off, hot flows of rock and ash rushed down the slopes.

USGS (Gunawan et al., 2019): a small phreatic eruption on 28 August 2010 from two vents in the south crater was the first in about 1,200 years; ash plumes reached altitudes of up to 5 km in early to mid-September; fumarolic emissions continued almost three years. The eruption that began on 15 September 2013 went through phases: phreatomagmatic (to 18 December 2013); a first dome with collapses and pyroclastic density currents; a lava flow (January to September 2014); a second dome (to July 2015); then dome collapses and ash explosions.

NASA (2014): collapses of the unstable summit dome sent pyroclastic flows at least 4.5 km down the slopes.

Scientists listen to the volcano with special tools.

They tell people when it is safe and when to stay away.

Two days after the 2010 eruption, a network of seismometers around Sinabung began recording its earthquakes, and a network of GPS stations was added in 2011, the USGS reports. Satellites watch it from space too.

On 31 August 2026, after a new eruption and a string of earthquakes, Indonesia raised Sinabung's alert to Level III, the second highest. People were asked to keep out of a zone around the summit.

USGS: monitoring by a telemetered seismic network began two days after the 2010 eruption, plus remote sensing; a near-field continuous GPS network was added in February 2011. NASA satellite instruments (Landsat 8, EO-1, Terra ASTER) imaged the ash plumes, lava flow and flow deposits in 2014.

CNN Indonesia (citing the national disaster agency BNPB): 85 volcanic earthquakes were recorded before the 31 August 2026 eruption; PVMBG raised the status from Level II (since 17 May 2023) to Level III; before this, Sinabung had last erupted in 2022.

Farmers grow coffee and chili peppers near the volcano.

Green forests grow nearby too.

NASA's satellite pictures show Sinabung surrounded by farms and forest. Coffee, chili peppers and other crops grow in plantations clustered at the foot of the volcano.

The dark green forests of Gunung Leuser National Park are also visible in NASA's satellite images of the area.

NASA Earth Observatory: Landsat 8 (6 March 2014) shows the volcano surrounded by farms and forest; ash from the 2013-2014 eruption coated the coffee, chili pepper and other plantations clustered at its foot and turned dark green forest tan in satellite images; a 2003 Landsat 7 image shows the villages, fields and the dark green forests of Gunung Leuser National Park.

Near a volcano, always do what the grown-ups in charge say.

Stay out of the danger zone.

When Sinabung's alert was raised in 2026, people and visitors were told not to go into villages that had been moved, within 3 kilometers of the summit, or within 6 kilometers on the south-east side. People living near rivers that start on the volcano were told to watch out for lahars.

The CDC says to follow the advice of local officials, have a plan to leave or shelter, and protect your lungs and eyes from ash.

CNN Indonesia (31 August 2026, BNPB): no activity in relocated villages, within a 3 km radius of the summit, or within 6 km in the south-east sector; residents near rivers rising on Sinabung should stay alert for lahars and follow BPBD directions.

CDC volcano safety: follow local officials' advice; plan to evacuate or shelter; an emergency kit with respiratory protection and goggles; ash can harm the respiratory tract (use an N95 respirator outdoors).