In a stormy Hawaiian sky in July 2017, streaks of red and blue lightning appeared to meet above a bed of white light.
The cameras of the Gemini North Telescope at the Gemini Observatory in Mauna Kea took a stunning image of the multi-colored light show. The National Laboratory for Optical-Infrared Astronomy Research (NOIRLab) released the photo on Wednesday as its “picture of the week.”
The lightning in the picture “appears so otherworldly that it seems like it must be a special effect,” NOIRLab said. It also released a zoomable version.
These colorful lightning phenomena are well known as red sprites and blue jets. They are extremely difficult to capture on camera: flashes last only tenths of a second and can be difficult to see from the ground, as they are usually obscured by storm clouds.
According to Peter Michaud, the education and engagement manager for the NOIRLab, astronomers from nearby Hilo are using the telescope’s cameras to remotely track the bad weather brewing near the observatory. The camera system takes a photo of the sky every 30 seconds.
“We’ve seen a few other examples of similar phenomena, but this was the best example of a lightning sprite in the upper atmosphere,” he told Insider.
Red, white and blue
Regular white lightning differs from sprites and jets in several ways. As regular lightning bolts shoot between electrically charged air, clouds, and the ground during storms, sprites and jets start at different locations in the sky and move into space. Their distinctive hues also set them apart.
The red sprites are super-fast bursts of electricity that crackle across the upper regions of the atmosphere – between 37 and 50 miles in the sky – and travel into space. Some sprites are shaped like jellyfish, while others, like the one in the Gemini Observatory image, are vertical columns of red light with winding tendrils. These are called carrot sprites.
Stephen Hummel, a dark sky specialist at McDonald Observatory, captured a spectacular image of a jellyfish sprite from a ridge of Mount Locke in Texas last July (below).
McDonald Observatory Dark Sky Specialist Stephen Hummel snapped a photo of this red jellyfish pixie from Mt. Locke, TX, July 2, 2020.
Stephen Hummel
“Sprites usually appear to the eye as very short, dark, gray structures. You have to look for them to spot them, and often I’m not sure I’ve seen one until I check the images in. the camera to confirm, ”Hummel told Insider. at the time.
Davis Sentman, who worked as a professor of physics at the University of Alaska at Fairbanks, came up with the name “sprite” for the red lightning phenomenon. He said the term was “well suited to describe their appearance,” as the word evokes the magical and fleeting nature of lightning. Sentman died in 2011.
Blue jets, on the other hand, are born closer to Earth than red sprites. These cone-shaped electric discharges are also brighter than sprites, and they explode from cloud tops. Peaks of storm clouds can be between one and 14 miles above the Earth’s surface; the blue jets continue to move skyward until they reach a height of about 30 miles, at which point they disappear. These jets travel at speeds of over 22,300 mph.
Sprites and jets can be seen from space
When regular lightning strikes the ground, they tend to release positive electrical energy which must be balanced with equal energy and opposite charge elsewhere in the sky. So sprites and jets are the electric shocks that balance the equation – that’s why these colorful lightning phenomena happen.
“The more powerful the storm and the more lightning it produces, the more likely it is to produce a sprite,” Hummel said.
Astronauts can occasionally spot sprites and jets from the International Space Station, 250 miles above Earth.
Astronauts photographed a red lightning sprite under the white light of a thunderstorm aboard the International Space Station in August 2015.
NASA
European Space Agency astronaut Andreas Morgensen captured elusive blue jets on video for the first time in color in 2015. He spotted the jets while filming a storm over the Bay of Bengal in India. Scientists then used the images in a 2017 study.
A blue jet recorded over a thunderstorm from the International Space Station.
Andreas Mogensen / ESA / NASA / YouTube
Morgensen’s observations “are the most spectacular of their kind,” the study authors wrote.
