Cyclones, blizzards, twisters. They all sound scary. But tephra -- that doesn't sound so bad. What exactly is tephra?

Tephra is actually the Greek word for ash, and refers to any particles and rocks that spew from a volcano during its eruption. The largest pieces of tephra will typically be deposited close to the site of the eruption while smaller particles can travel for miles and miles.

Asked by Tom Cohen · Last updated 5 years ago · 4.6K views