Lava from a volcano

Destructive eruption of volcano Nyiragongo

22 May 2021, 18:00 UTC to 23 May, 17:15 UTC

Lava from a volcano
Lava from a volcano

In the evening of 22 May 2021 the volcano Nyiragongo started to erupt, threatening life and property, in particular in the nearby town of Goma in the Democratic Republic of the Congo.

Last Updated

10 June 2022

Published on

08 June 2021

By HansPeter Roesli (Switzerland)

Thousands of people fled their home after the mass evacuation of Goma and more than 30 people were reported to have died — mainly due to traffic accidents during the evacuation.

While the eruption was calamity for the local people, its view from space was not very impressive. Due to the local climate, heavy clouds shrouded the area most of the time. Nevertheless, in the Ash and SO2 RGBs from Meteosat-11 signals of SO2 (green) first, then ash (red) and finally an SO2 ash mix (orange) were observed among the clouds.

Met-11 Ash & SO2 RGB 22 & 23 May 2021
Figure 1: Meteosat-11 Ash and SO2 RGBs from various times on 22 and 23 May.

The Meteosat-11 imagery (Figure 1) shows these episodes at 18:30 UTC (SO2) on 22 May, and at 07:15 UTC (ash) and 17:00 UTC (ash and SO2 mix) on 23 May. The Meteosat-11 loop (Figure 2) shows the evolution through these phases.

Figure 2: Meteosat-11 Ash and SO2 RGB, 22 May 18:00-23 May 17:15 UTC


In the Meteosat-8 and Sentinel-3 imagery in Figure 3, the middle panel zooms in on the eruption using a Sentinel-3A OLCI True Colour RGB on 23 May at 07:32 UTC. Although there are no clear signs of the eruption, the brown-grey hues north of the white cloud mass might indicate the presence of an ash veil. This is confirmed by the Meteosat-8 Ash and SO2 RGB in the right panel, where a red ash plume extends towards the north-west flanked by green SO2. However, on the Meteosat-8 Natural Colour RGB in the left panel no signs are visible.

Met-8 and S3a imagery, 23 May 2021
Figure 3: Meteosat-8 Natural Colour RGB (left), Sentinel-3A OLCI True Colour RGB (middle) and Meteosat-8 Ash and SO2 RGB (right), 23 May 07:32 UTC.


Figure 4 is a combination of the Suomi-NPP VIIRS Day-Night band on 22 May at 22:47 UTC in black-and-white and the temperature in false colours measured in NIR3.7 band. It shows the glare from lava flows (light grey) on the flanks of Nyiragongo and the hot spot over its peak (yellow, temperature >350 K).

SNPP Day-Night Band 22 May 2021
Figure 4: Suomi-NPP DNB and M12, 22 May 22:47 UTC.

Additional content

Mount Nyiragongo: DR Congo residents flee as volcano erupts (BBC News)
Democratic Republic of the Congo - Nyiragongo Volcano Situation Report #1 - May 27, 2021 (Relief Web)
Nyiragongo volcano (Volcano Discovery)