Health

Expert discusses the U.S. food safety system

Contaminated food causes 48 million illnesses, 128,000 hospitalizations and 3,000 deaths each year in the United States. In his new book, "Outbreak: Foodborne Illness and the Struggle for Food Safety," published by the University ...

Health

Sunrise and sunset guide daily activities of city-dwellers

Despite artificial lightning and social conventions, the dynamics of daylight still influence the daily activities of people living in modern, urban environments, according to new research published in PLOS Computational ...

Neuroscience

'Lightning bolts' in the brain show learning in action

Researchers at NYU Langone Medical Center have captured images of the underlying biological activity within brain cells and their tree-like extensions, or dendrites, in mice that show how their brains sort, store and make ...

Health

Outdoor enthusiasts need a lightning plan

(HealthDay)—Those partaking in outdoor sports and activities need to be aware of the threat posed by lightning and take appropriate safety measures, experts say.

Health

Boys go camping, get shock of their lives

Eight-year-old twin boys, camping in a backyard tent, received penetrating blast injuries when a bolt of lightning struck a transformer near their tent, sending them to the emergency department for treatment. The extremely ...

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Lightning

Lightning is an atmospheric discharge of electricity accompanied by thunder, which typically occurs during thunderstorms, and sometimes during volcanic eruptions or dust storms. In the atmospheric electrical discharge, a leader of a bolt of lightning can travel at speeds of 60,000 m/s (130,000 mph), and can reach temperatures approaching 30,000 °C (54,000 °F), hot enough to fuse silica sand into glass channels known as fulgurites which are normally hollow and can extend some distance into the ground. There are some 16 million lightning storms in the world every year.

Lightning can also occur within the ash clouds from volcanic eruptions, or can be caused by violent forest fires which generate sufficient dust to create a static charge.

How lightning initially forms is still a matter of debate: Scientists have studied root causes ranging from atmospheric perturbations (wind, humidity, friction, and atmospheric pressure) to the impact of solar wind and accumulation of charged solar particles. Ice inside a cloud is thought to be a key element in lightning development, and may cause a forcible separation of positive and negative charges within the cloud, thus assisting in the formation of lightning.

This text uses material from Wikipedia, licensed under CC BY-SA