What is a ‘sprite’ which was spotted towering over the US by NASA

High above thunderclouds, where Earth’s atmosphere transitions into space, some strange and fleeting flashes of red light can sometimes be spotted in silence. But what are these? Alien signals or some undiscovered phenomenon?These flashes of red lights are known as red sprites,and such bright, jellyfish-like bursts have fascinated pilots and puzzled scientists for nearly a century.

Unlike lightning that strikes downward, red sprites shoot upward into the sky, disappearing in just milliseconds. They’re so quick and hard to see that, for decades, many dismissed them as pilot myths or optical illusions.But with space-based observations and improved camera technology, came into some limelight. Astronauts aboard the International Space Station (ISS) managed to capture stunning images of red sprites, offering a clearer look into these high-altitude discharges.

How long has this phenomena existed for?

For almost 100 years, pilots reported seeing strange flashes of red light above thunderstorms. While many atmospheric scientists were skeptical, the mystery took a turn in 1989 when a photo accidentally captured the first clear image of a red sprite. Since then, the search for understanding these elusive phenomena has grown and a view from the space above has become one of the best places to look.

Astronauts aboard the International Space Station captured rare images of red sprites above thunderstorms over North and Central America. According to NASA’s Scientific Visualization Studio (SVS), the first sprite was photographed from over northwest Mexico, while the crew looked northeast.

It appeared more than 2,200 kilometers away, likely above Missouri or Illinois. “The sprite shoots up to the greenish airglow layer, near a rising moon,” NASA SVS said. The bright lights of Dallas, Texas, were visible in the foreground.Just under three minutes later, while the ISS was over Acapulco, Mexico, astronauts captured a second sprite over a storm near the coast of El Salvador. This one, about 1,150 kilometers (710 miles) away, showed more detail due to the closer distance.

The yellow glow in the image comes from city lights shining through clouds.

What exactly are these red sprites?

Red sprites are massive electrical discharges that can go up to 100 kilometers above Earth’s surface. They’re not lightning in the usual sense. Unlike the hot, jagged lightning we see during storms, sprites are “cold plasma”, more like a giant version of what one can see in a fluorescent light tube.“Because their pictures are so rare, very little is known about sprites,” European Space Agency astronaut Andreas Mogensen said in a ESA TV segment in 2016.

They’re extremely brief, lasting only milliseconds, and are usually hidden behind thunderclouds, making them hard to study from the ground.According to NASA, sprites occur when strong lightning discharges interact with Earth’s ionosphere. As the discharge moves through the atmosphere and hits nitrogen molecules, it produces a reddish glow. These red flashes are part of a category called “transient luminous events,” which also includes blue “jets” and red “elves”, each a different form of upper-atmosphere energy release (ESA).