Icelandís Eyjafjallajokull volcano erupts for the first time in 190 years on 29 March, 2010, opening a 500m (1,640ft) fissure. The eruption produces lava, a volcanic plume, and steam from vapourised snow.
An infrared image from a Nasa satellite shows the Eyjafjallajokull volcano.
The images show a white plume extending roughly 70 km (40 miles) east, taken a few hours apart. Nasa says the plume is steam caused by molten lava reaching the surface beneath the 200m (700ft) thick glacier.
The continuing eruptions send ash and steam thousands of feet into the sky before drifting off across Europe. Much of the airspace over Europe is closed because of concern for aircraft safety.
As the ash cloud spreads over northern Europe, thousands of air passengers are left stranded as the shutdown continues.
By 17 April the plume from the volcano was still reaching heights of about 6,096m (20,000ft) and spreading west as well as east.
The volcanic eruptions start to die down after 21 April, giving the airline industry a chance to get back to normal service.
But further eruptions send more ash into the air and once again the skies are closed to air traffic. The cloud even reached Spain and North Africa at times. Disruption continues sporadically as the intensity changes.
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