The aerial video peers right into the crater of Mount Agung, which has been intermittently erupting and spewing out ash since late last month. 

The drone footage of the volcano reveals a lava dome within the crater but there was no sign of the red glow which has occasionally been spotted over summit at night. 

The unique perspective showed how magma has partly filled the crater and emphasised the sheer size of 3,000m strato-volcano on the popular tourist destination of Bali.  

Magma Indonesia, which monitors volcanoes, said that the drone was flown over the volcano to find out what was happening in the crater without putting lives at risk.  

It tweeted: “Our drone captured the latest condition of Mount Agung crater on 14 December 2017 16:00 local time (utc+8).” 

Sutopo Purwo Nugroho said that the footage showed that the new lava dome was filling a third of the crater. 

But he said that the lava dome was now smaller when the volcano erupted in late November, forcing the closure of airports on Bali and Lombok. 

He added that the rate of magma coming out of the volcano has been slowing down over the past two weeks since November 30.  

During the eruption in November, ash poured out of the crater and destructive mudflows, known as cold lava, poured down the slopes of the volcano. 

The Oregon State University website said that lava domes are an awe inspiring sight despite being less spectacular than their flowing counterparts. 

The website said: “Lava domes are formed by viscous magma being erupted effusively onto the surface and then piling up around the vent. 

“Like lava flows, they typically do not have enough gas or pressure to erupt explosively, although they may sometimes be preceded or followed by explosive activity. 

“However, unlike lava flows, the lava that forms domes is often to thick and sticky to flow very far, and thus instead pile up thick and high around the vent.”