The sky is a mystery in itself, and despite the daily routine of observing it every day, it can always surprise us with phenomena that defy our understanding of it. The red sprites, also called sprite rays, are precisely one of these spectacles that we rarely have the privilege of observing, but in a stroke of luck, Chile was the scene of one of them, and we were able to witness it through the photographs taken by the European Southern Observatory (ESO) in the Atacama Desert.
The red sprites are flashes of reddish coloration that spread like brushstrokes in the sky. They are completely different from the rays we are used to, as there are even some that resemble giant jellyfish that sail across the celestial vault. They are not especially rare, but they are very difficult to see, which is why when a red sprite crosses the sky and you are lucky enough to capture it on video or photography, it attracts a lot of attention.
Red sprites over Atacama
The photograph taken recently in the Atacama Desert, one of the best places with enough darkness available to observe the cosmos, has gone around the world. It is so impressive that it almost looks like a painting showing the starry horizon in greenish tones and the background on the right, a set of sprite rays that resemble brushstrokes of Van Gogh himself.
Although the image shows the red sprites above the horizon, the reality is that they are at a much higher altitude. They are only seen at this limit due to the position and perspective of the ESO camera on the 3.6-meter telescope platform at La Silla.
ESO explained that the composition of the image, in addition to showing the red sprites, also reveals another extraordinary phenomenon in the sky. The greenish background is known as the airglow effect and is generated by the fact that during the day sunlight pulls electrons away from nitrogen and oxygen in the atmosphere, but at night these electrons recombine with atmospheric atoms and molecules, causing them to glow.
This is one of the most impressive images showing the red sprites in the sky, which are rays that are generated at high altitudes in the sky, and for this reason, they can rarely be seen with the naked eye.
Story originally published in Spanish in Ecoosfera
