At an altitude of around 80–90 kilometres above the Earth, mysterious green flashes sometimes occur; these resemble ghosts and appear above powerful thunderstorms. This rare atmospheric phenomenon has been dubbed «Green Ghosts». It was first recorded by amateur photographers in 2019, but the origin of this unusual glow remained the subject of scientific debate for a long time. In 2026, international teams of researchers published new studies explaining how electrical discharges above thunderclouds can cause oxygen atoms to emit green light.
- Rare luminous phenomena, known as ‘green ghosts’, appear above powerful thunderstorms.
- The phenomenon is observed mainly at an altitude of 75–95 kilometres.
- Green ghosts appear above the red sprites.
- Research carried out in 2026 attributes the glow to excited oxygen atoms.
What are green ghosts and how do they appear?
Green ghosts are among the unusual atmospheric phenomena that occur in the upper layers of the atmosphere following powerful lightning strikes. Unlike ordinary lightning, which forms inside clouds or between a cloud and the ground, these lights occur tens of kilometres above thunderstorm systems.
They are related to red sprites — brief electrical discharges that sometimes resemble giant jellyfish with long tentacles. A sprite usually lasts only a few milliseconds. However, a faint greenish glow sometimes lingers above its upper part, which can persist for hundreds of milliseconds. It is this unusual effect that has been dubbed ‘Green Ghosts’.
The title is also a scientific abbreviation for Green emissions from excited oxygen in Sprite Tops — green light emitted by excited oxygen in the upper part of the sprites.
Scientists have found an explanation for the mysterious green light
On 31 July 2026, the scientific journal *Journal of Geophysical Research: Space Physics* published a study by an international team led by Sébastien Celestine from the University of Orléans in France.
Scientists have developed a model of the chemical reactions that take place in the upper atmosphere following electrical discharges. The results have shown that one of the main mechanisms behind the formation of the green glow may be the transition of excited oxygen atoms to a lower energy state.
During this process, the atoms emit light with a wavelength of approximately 557.7 nanometres — in the green part of the visible spectrum. Similar oxygen emission is also observed in the aurora, although the mechanisms behind the two phenomena differ.
Researchers have found that at altitudes below approximately 90 kilometres, excited oxygen can be formed as a result of oxygen molecules being split by electrons. Above 90 kilometres, the transfer of energy from excited nitrogen molecules to oxygen atoms plays an important role.
Thus, a powerful thunderstorm is capable of triggering complex physical and chemical processes at high altitudes, where the atmosphere is already extremely thin.
Why are green ghosts so rare?
Although thunderstorms occur constantly on Earth, green flashes are observed much less frequently than ordinary lightning. Researchers attribute this to a combination of several factors.
For visible glow to occur, sufficiently powerful electrical processes are required to excite oxygen atoms in the upper layers of the atmosphere. At the same time, the ambient temperature affects how long these atoms can remain in an excited state. If an atom loses energy as a result of collisions with other particles, it may not have time to emit a green photon. This is why, even in the presence of a powerful sprite, the green ghost may not appear or may remain too faint to be observed. The height of the ionosphere and the characteristics of the electric field above the thunderstorm play a distinct role.
The first green ghosts were spotted by amateur photographers
Interestingly, it was not only professional researchers but also amateur photographers who got involved in studying this atmospheric phenomenon. One of the first to capture the unusual green glow in 2019 was a storm chaser Genk Shima. He also photographed similar phenomena and Paul Smith, who later became a co-author of the research paper.
In particular, on 25 September 2019, Paul Smith used a Sony A7S camera to capture an unusual glow above a thunderstorm near the city of Wichita in the state of Kansas. At the same time, The photographer was approximately 217 kilometres away from the lightning strike, which the researchers have linked to the emergence of the phenomenon.
Analysis showed that the lightning strike in question had a peak current of around 100,000 amperes. This observation formed part of a scientific study published in 2026.
Traces of metals have even been found in green ghosts
The history of research into this phenomenon proved to be even more fascinating following a discovery published in 2023 in the journal *Nature Communications*. It was then that Spanish scientists obtained, for the first time, a detailed spectrum of one of the green ghosts.
As well as oxygen emissions, they detected spectral signatures of iron, nickel, nitrogen and other components. The scientists linked the presence of these metals to meteoric material entering the Earth’s atmosphere and leaving behind atoms of various elements.
It follows, then, that some green glows may have a more complex chemical composition than early models had predicted.
Research carried out in 2026 strengthened the case for the role of reactive oxygen species, but did not rule out the contribution of other substances. The exact balance between the various mechanisms still requires further observation.
Can you see green ghosts over Ukraine?
In theory, such atmospheric phenomena can occur above powerful thunderstorm systems in various regions of the world. However, it is extremely difficult to see the green ghost with the naked eye due to its faint brightness and the short duration of its glow.
To document this phenomenon, high-sensitivity cameras are usually used, which enable the night sky above distant thunderstorms to be photographed.
Photographers need a dark sky, suitable weather conditions and an unobstructed view of the upper part of the thunderstorm system. That is why professional photographers often capture such phenomena hundreds of kilometres away from the thunderstorm.
There is currently insufficient confirmed data on the frequency of green ghosts appearing over Ukraine.
