‘Red jellyfish’ seem on the ocean after a storm sparking alien invasion theories

The unusual red shapes, which seemed to hover over the ocean after recent storms, prompted confusion and fascination over the internet in equal measure

Striking images of bright “ red jellyfish ” appearing in the sky above storm clouds have sparked a wave of speculation online, with some social media users even floating theories about alien activity.

The unusual red shapes, which seemed to hover over the ocean after recent storms, prompted confusion and fascination in equal measure. NASA has now stepped in to explain the science behind the dazzling displays.

The phenomenon is entirely natural and known as a red sprite lightning discharge. These so-called jellyfish lights are rare electrical flashes that burst high above powerful thunderstorms.

Unlike normal lightning, which shoots downward towards the ground, sprites fire upwards, illuminating the sky in a vivid crimson glow.

Their distinctive colour is produced when the intense electrical energy interacts with nitrogen in the upper atmosphere.

The flashes occur in the mesosphere, around 50 to 90 kilometres above the Earth’s surface, and although they last only a few milliseconds, they often form elaborate, branching shapes that resemble jellyfish, with a bright rounded head and long glowing tendrils.

It is this unusual appearance that has fuelled online theories, but scientists say there is nothing otherworldly about the lights. They are simply difficult to observe because they require extremely strong thunderstorms to form and are usually visible only from space or with specialised cameras on the ground.

Astronauts aboard the International Space Station have been among those to capture the most striking images.

During a recent pass above a major storm, one astronaut photographed a particularly vivid sprite, revealing details invisible from the surface. Their images show the full beauty of these electrifying structures, offering an extraordinary perspective.

Citizen scientists have also played a role in documenting the lights. Through NASA’s Spritacular programme, people from around the world have submitted thousands of photos, allowing researchers to analyse the shapes, patterns and frequency of red sprites far more accurately. This collective effort has been crucial in debunking the rumours that surged after the sightings went viral.

These spectacular displays triggered a flood of posts referring to them as “mysterious jellyfish lights” or even “alien signals,” prompting NASA to issue a clarification.

The agency emphasised that sprites are well-understood atmospheric events and confirmed that no extraterrestrial activity is involved.

Scientists have studied their colour, structure and behaviour for decades, all of which align perfectly with known electrical processes in the upper atmosphere.

Beyond their striking appearance, red sprites provide valuable scientific insight. They help researchers understand how energy transfers through the atmosphere during strong storms, offering data that may improve weather models and lightning prediction.

Although fleeting, they can also influence long-distance electromagnetic disturbances in the upper layers of the sky.

NASA stressed that these jellyfish lights are not a threat, occurring far above commercial flight paths and forming naturally above storm systems.

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