Detailing atmospheric halo “inventory” is frequently seen as aerial light illusions from known sources as well as illuminating rare halos, including halos of origins that are currently a mystery.
The halos are caused by the accumulation of water ice crystals less than 10 micrometers in size in the atmosphere. The qualities of these atmospheric illusions such as their color or whether they have white arcs, spots or rings, are determined by the shape and direction of the ice’s scattering and the path of light it takes toward these crystals. Often, the type of crystal behind the scattering can be determined by the shape of the halo it creates.
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These atmospheric fantasies have been documented by mankind since at least the Babylonian period – which began around 1895 BC – when phenomena were detailed on cuneiform tablets. However, thanks to the availability of cameras as a result of the proliferation of cell phones, scientists have never had much data on these phenomena at their fingertips.
In addition to an extensive catalog of auras, this new research – based on observations collected through the end of 2021 – highlights gaps in the study of phenomenology. The authors responsible for the inventory also developed promising methods for additional monitoring and processing of the collected data, and urged the public to participate in the recording of these phenomena using their phones and digital photography.
The complete catalog divides the phenomenon into 119 different types and also details the conditions such as temperature and humidity required to create it.
Halos seen at least once a year have been defined as ‘commonly observable’ and are typically formed by scattering, refracting and focusing of light from the Sun or being reflected off the Moon by hexagonal ice crystals in an unorganized, horizontal or vertical direction.
Another category – “rare halos” – which includes atmospheric illusions that account for only about one percent of all observations, is further divided into halos of known origins and those of unknown and exotic sources.
“As a rule, halos are formed as a result of the interaction of light with hexagonal crystals of water ice,” a scientist at the Finnish Geospatial Research Institute and Ph.D. Jarmo Moilanen, a student at the University of Helsinki, said in a statement (Opens in a new tab). “However, some of the strange auras documented cannot be explained in this way.”
Moilanen, who developed the inventory of atmospheric halos with University of Helsinki professor, Maria Griesvich, cited some examples of such strange halos. “Mysteries of the origin of ellipticals and bottling rings (Opens in a new tab) It has not been resolved since its discovery at the beginning of the 20th century,” the researcher said. Among the mysteries is the so-called Mulanin Arch (Opens in a new tab)which I first discovered in 1995.”
The researchers suggest that the key to producing mysterious atmospheric auras could be ice crystals of irregular shapes or crystals of other minerals scattered in the air.
Research suggests that the unusual shape of strange halos is due to man-made factors, such as emissions in the atmosphere or strong electromagnetic fields from high-voltage power lines, Griesvich said. She added that these factors can disrupt the orientation of ice crystals in the air, which may lead to the appearance of strange halos.
“To unravel such mysteries, samples were collected of ice crystals that form strange halos, especially in the atmosphere, but this experiment also gave more questions than answers,” Griesvich said in the statement, adding that atmospheric halos observed around other planets could potentially Be the one used to unravel this mystery.
This includes halos that have been observed and documented in the Martian atmosphere, which can also be used to better understand the red planet’s diffuse thin atmosphere.
“This observation proves that clouds of hexagonal crystals of water ice or other minerals are present in the Martian atmosphere,” says Maria Griesvich. “There are suggestions that halos could be formed by carbon dioxide crystals.”
She added that mathematical modeling of the factors that could lead to the formation of the corona could provide valuable information about the state of the Martian atmosphere.
The duo’s research was published in Journal of Quantitative Spectroscopy and Radiological Transport. (Opens in a new tab)
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