How 50-Mile-High Jets of Lightning Shoot Toward Space

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By Jane J. Lee May 19, 2011 | 3:36 pm | Categories: Physics


Gigantic jets of lightning that shoot upward toward space can tower 50 miles above the Earth’s surface. Until now, we knew very little about the conditions that set them off or how they form.

Close observations of two gigantic jets in September 2010 enabled researchers to map out the electrical-charge imbalances that spawned this particular type of lightning.

“For the first time, these observations give us details of what lightning channels are doing when they form gigantic jets,” said lightning scientist Steven Cummer of Duke University, co-author of research published May 5 in Geophysical Research Letters.

Lightning occurs when a spark travels from either a negatively charged or positively charged area of a thundercloud to an area of opposite charge. Thunderclouds tend to accumulate positive charges in their upper portions, while the middle and lower levels accumulate negative charges.

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