Some 600, 000 years ago, it erupted and left an ash layer 10 feet deep as far as 1, 000 miles away.

FORBES: Fact and Comment

Some 600, 000 years ago, it erupted and left an ash layer 3 meters deep as far as 1, 600 kilometers away.

FORBES: Fact & Comment

Metop's suite of instruments retrieve a range of data - from the temperature and water content of the different layers in the atmosphere to the speed of the winds whipping across the ocean, and from the health of the ozone layer to the spread of volcanic ash plumes across the sky.

BBC: Weather satellites and the gathering storm