By Stephanie Dwilson | 2026-06-11

Space agencies across the world are studying faster-than-lightning events in space that are still, in many ways, mysterious.

Called Transient Luminous Events (TLEs) these colorful flashes of light are created by thunderstorms, but until recently they were rarely documented because they only occur above the clouds.

These weather events, which may only last for milliseconds, have been given a variety of names based on their shapes. Among the most common are:

Red sprites: Beautiful electrical discharges associated with cloud-to-ground lightning that look like upside-down jellyfish. These may extend up to 60 miles from a cloud top and only last a few seconds.

They can only be seen at night, and rarely with the human eye.

Elves: Concentric expanding rings that may extend up to 300 miles across. These last less than a thousandth of a second and occur above active areas of cloud-to-ground lightning. They were first discovered in 1992.

Blue jets: Blue flashes that move up from the clouds. They aren’t directly associated with cloud-to-ground lightning like sprites, but do emerge from the top of thunderclouds.

Blue jets may extend up as far as 25 to 35 miles. They’ve been witnessed by pilots.

Thanks to satellites, digital cameras and enthusiastic scientists and amateur photographers, we’re now understanding more about these fanciful shapes of light.

Here’s a look at some of the recent discoveries and methods being used to study TLEs like red sprites.

Astronaut captures red sprite

Scientists believe sprites occur when positively charged lightning interacts with nitrogen in the atmosphere, creating red flashes of light, according to NASA.

Many have tendrils that resemble those of jellyfish, but reaching upwards, into space.

In June 2024, an astronaut with the Expedition 71 crew on the International Space Station (ISS) captured one of these elusive red sprites in a sequence of photos.

The photos were taken with a Nikon Z9 digital camera using a focal length of 28mm. The images were then stitched together to create a 19 second timelapse of the event.

ESA monitors for TLEs

Today it’s easier to capture TLEs thanks to the European Space Agency's Atmosphere-Space Interactions Monitor (ASIM). The ASIM is installed on the International Space Station’s European Columbus module.

It consists of optical cameras, photometers, and an X- and gamma-ray detector that work together to look for transient electrical discharges occurring in the upper atmosphere during storms.

The hope is that the ASIM will gather data over time to help make TLEs less mysterious.

Red sprites over South Asia

A study published in Advances in Atmospheric Sciences in 2025 documented an outbreak of 105 red sprites over South Asia in May 2022. The sprites were recorded by two amateur photographers.

These photographs revealed that thunderstorms can indeed produce numerous, complex types of sprites. The study proposed methods of examining these storms and luminous events in more detail in the future.

Of particular interest: at least four of the observed TLEs were very rare green luminous events known as "ghosts."

Ghosts occur on the top part of red sprites and are one of the more recently discovered types of TLEs. They occur for only milliseconds at a time and are rarely seen.

NASA's TLE database

NASA is crowdsourcing studies of TLEs by inviting photographers from across the world to contribute their TLE observations to a single database called Spritacular.

To participate, photographers must register an account, study the blog’s resources tab to learn how to capture TLE images, and then submit any observations, photos or videos to the website.

The website has gathered 422 observations to date, and 933 volunteers from 22 countries. Two images from Spritacular volunteers were featured in NASA’s 2025 Science Calendar.