A NASA image reveals a strange circular phenomenon in the sky – DW – 04/03/2024

At the end of January this year, the Moderate Resolution Imaging Spectroradiometer (MODIS) was launched on the Terra satellite of a pot It was seized Strange phenomenon It orbits over the Gulf of Mexico, not far from the west coast of Florida.

How do you have it? Such an unusual look They do not resemble clouds at all, and some believe that they may be flying saucers or other anomalous phenomena without a scientific explanation. However, they are better known: hollow clouds (also called hole or hole clouds).

They are formed by the passage of aircraft

Cavum clouds are so large that they can be seen from Earth or space. Scientists have documented them since 1940, but only 15 years ago it was possible to find an explanation of how they formed.

He says that these circular clouds with a hole in the middle are the result of “aircraft moving across banks of cumulus clouds.” Explanatory statement From NASA.

“Supercooling” of clouds

Cavum clouds do not have the same characteristics as regular clouds. These consist of very cold liquid water droplets, which remain in this form at temperatures below the typical freezing point of water (0°C).

“Supercooling may seem strange, but it routinely occurs in Earth’s atmosphere,” the NASA report said.

He added: “Cumulus clouds, which cover about 8% of the Earth's surface at any time, consist mostly of liquid water droplets that are very cold to a temperature of about -15 degrees Celsius.”

This intense cooling is only possible “when the water droplets are exceptionally pure and lack particles such as dust, fungal spores, pollen or bacteria, around which ice crystals normally form.”

How are hollow clouds produced?

When aircraft wings and turbines pass through clouds, a process called adiabatic expansion occurs, which cools the water by another 20 degrees Celsius or more, bringing the liquid droplets to their freezing point. These ice crystals, called virga, gain weight and begin to fall from the sky, leaving a hole in the clouds.

According to a NASA report, any aircraft crossing the clouds at a shallow angle can cause this phenomenon. Furthermore, since more than 1,000 flights depart from Miami Airport every day, it is very likely that hollow clouds will form in the area when the necessary weather conditions are present.

The Terra satellite aims to study changes in the Earth's atmosphere and the effects of climate change. Scientists use data collected by the satellite to map the impact of human activity and natural disasters.