Chamoli disaster: 'It hit the valley bottom like 15 atomic bombs

As was the case with the Chamoli accident in February, when a Himalayan mountain's slope collapsed and crashed into the valley below.

It sparked off a chain reaction of devastation that claimed the lives of over 200 people and ruined hydro-electric infrastructure worth hundreds of millions of dollars.You may have seen some of the shared mobile phone footage at the time. A terrifying wall of sludge is rushing downslope, sweeping everything in its path away.

A full analysis of what transpired has now been released by an international collaboration of more than 50 researchers. It uses a variety of data sources, including satellite photos and field observations.

It's a depressing read with numbers that, to be honest, are nearly unfathomable

The accident occurred near the summit of the 6km-high Ronti Peak in the Chamoli region of Uttarakhand, India.

A 500-meter-wide, 180-meter-thick chunk of glacier-covered rock suddenly gave way.

According to the researchers, about 27 million cubic metres of material were poured into a minute-long plunge that included a brief period of complete freefall.

To put this volume in perspective, it is around ten times the size of Egypt's Great Pyramid of Giza.

The energy produced by the mass when it hit the Ronti Gad valley floor was comparable to 15 Hiroshima atomic bombs.