المملكة: Jeddah Astronomy: Glowing blue clouds at the edge of space reveal secrets about meteors

He explained that these clouds are usually observed in high latitudes, and their first seasonal appearance often occurs during late May or early June, where very fine ice crystals form and adhere to meteor dust particles suspended in the upper layers of the atmosphere. Atmospheric clouds appear as glowing blue ribbons floating at the edge of space.

Thin ice packs

Abu Zahra pointed out that the luminous night clouds are thin ice packs that form at high altitudes, and for a long time scientists have been unable to fully explain the mechanism of their formation. However, recent studies have revealed that these clouds form when temperatures in the highest layers of the atmosphere drop to levels that allow water vapor to freeze around tiny particles resulting from the burning of meteors, pointing out that about 3 percent of the components of each ice crystal in these clouds originate in what is known as meteor smoke.

He added that the ice crystals in these clouds are formed around extremely small meteor dust particles whose size ranges between 20 and 70 nanometers, in While the ice crystals found in thin clouds in the lower layers of the atmosphere are between 10 and 100 times larger as a result of the abundance of water vapor at lower altitudes.

Fine rocks

Abu Zahra explained that the interior of the solar system is filled with small bodies of various sizes, from fine rocks to microscopic dust particles, and that the Earth sweeps away several tons of these materials daily. When meteorites enter the atmosphere and burn due to friction, they leave behind clouds of fine particles suspended at a height ranging between 60 and 100 kilometers above the Earth’s surface, becoming nuclei around which ice crystals that form luminous night clouds gather.

He pointed out that these clouds have been observed since the nineteenth century in the Arctic regions, but recent decades have witnessed their appearance in regions farther south, which has prompted scientists to study the possible relationship between their increased visibility and changes. Global climate change, in addition to the rise in methane levels in the atmosphere.

A chain of reactions

Abu Zahra explained that methane is one of the most important greenhouse gases, and when it reaches the upper layers of the atmosphere, it is oxidized through a complex series of chemical reactions, producing water vapor, which provides a more suitable environment for the formation of ice crystals for these glowing clouds. He added that studying this phenomenon may help scientists understand the changes occurring in the Earth’s atmosphere and monitor the effects of climate change in the long term.

As for the reason for the distinctive blue color of these clouds, he explained that the small size of the ice crystals makes them more capable of scattering the short wavelengths of blue light compared to the long wavelengths of red light, and therefore these clouds appear a striking silvery blue color when viewed from the surface of the Earth after sunset.

Scientific Studies

Rais pointed out The Jeddah Astronomer pointed out that scientific studies have also shown that luminous night clouds may become denser and brighter during periods of minimum activity in the solar cycle, as the relative coldness at the top of the atmosphere leads to enhanced formation of ice crystals around meteor smoke particles. In most countries of the Arab world, it is extremely rare due to the geographical distance from the polar regions.

Sporadic observations

Abu Zahra added that recent decades have witnessed the recording of sporadic observations of these clouds at latitudes lower than usual, especially in some regions of southern Europe and the Mediterranean basin, and it is believed that climate changes and the increase in water vapor in the upper layers of the atmosphere may contribute to the expansion of their appearance towards regions farther from the poles.

As for Saudi Arabia, the possibility Their monitoring remains very weak, and any luminous clouds that appear at night are mostly high clouds illuminated after sunset or other weather phenomena, and not true luminous night clouds.

He concluded by saying that luminous night clouds still carry many scientific secrets despite the great progress in their study, but what is certain so far is that meteor smoke coming from space plays a pivotal role in the emergence of these unique clouds, while the exact reason behind their increase in brightness and spread remains. A subject for ongoing scientific research and study.