Dark clouds gather over the sky, heavy rain falls, and lightning crackles. The bolt, instead of striking the ground or zipping between clouds, blasts straight upward, shooting 50 miles (80 km) into the sky, grazing the bottom of space.
This type of bolt is known as a gigantic jet. Rare and powerful, they occur only 1,000 times a year and emit more than 50 times as much energy as a typical lightning bolt - and now, scientists have discovered the single most powerful gigantic jet.
Researchers analyzed a giant jet that shot out of a cloud over Oklahoma in 2018 in a study published 3rd of August in Science Advances. In analyzing the jet's radio-wave emissions using satellite and radar data, scientists determined that the bolt moved 300 coulombs of energy from the cloud to the lower ionosphere — the layer of charged particles that separates Earth's upper atmosphere from space — which is roughly 60 times as much energy as a typical lightning bolt.
"The charge transfer is nearly double the previous largest by a gigantic jet and is comparable to the largest ever recorded for cloud-to-ground strokes," the researchers wrote in the study.
Three sequential photos of a 'gigantic jet' lightning bolt blasting out of the top of a cloud over Oklahoma, and shooting directly into space. (Image credit: Chris Holmes)
It took an equally massive stroke of luck to capture such detailed data on the massive strike of lightning. With a low-light camera, a citizen scientist in Hawley, Texas filmed the jet on the 14th May, 2018, as it shot out of a cloud top before connecting with charged particles in the ionosphere, some 96 km above the ground.
According to scientists analyzing the footage, the jet struck very near the centre of a lightning mapping array (LMA) - a network of ground-based radio antennas used to map lightning strikes. A weather radar system and a satellite network were also within range of the jet.
Researchers studied the gigantic jet's size, shape, and energy output in unprecedented detail using these sources. The researchers found that the jet's highest-frequency radio-wave emissions (the kind that LMAs are designed to detect) came from small structures called streamers, which develop at the very tip of a lightning bolt and create a "direct electrical connection between the cloud top and the lower ionosphere," according to Levi Boggs, the lead study author.
Electricity flowed most strongly behind the streamers, in a section known as the leader. Moreover, the data showed that while the streamers were relatively cool at about 204 degrees Celsius, the leader was scorching hot, reaching more than 4,426 degrees Celsius. According to the researchers, this discrepancy applies to all lightning strikes, not just gigantic jets.
Is there a reason why lightning sometimes blasts up instead of down? Lightning is likely to be prevented from escaping because of some type of blockage, but scientists aren't completely certain what that is. Gigantic jets are typically observed in storms that don't produce many cloud-to-ground lightning strikes, the team added.
Space lightning mystery: 'Gigantic' jet bursts found shooting 80km into cosmos (Image: NASA/ Hung-Hsi Chang)
For whatever reason, there is usually a suppression of cloud-to-ground discharges," Boggs said. "In the absence of the lightning discharges we normally see, the gigantic jet may relieve the buildup of excess negative charge in the cloud."
Tropical regions are also the most frequently reported to have giant jets, the team said. Considering the jet wasn't connected to a tropical storm system, it was all the more impressive when it broke the record over Oklahoma. Understanding these epic, upside-down lightning strikes will require further research - and a lot of luck.
QUESTION: Is the study worth the investment?
Let us know in the comments and keep thrusting Australia into the deep unknown…
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1 comment
Could the fact that Oklahoma is in Tornado Alley be part of the reason why it occurred?