In addition to the Moon there are more celestial bodies around the Earth: what are the Kordylewski Clouds and what do we know about their existence
After its theoretical confirmation in 2018, the National Geographic magazine published an article with the suggestive title of “The Earth has two extra ‘moons’, hidden”. Our satellite was no longer alone, as the Kordylewski clouds, first observed in 1961 by the Polish astronomer Kazimierz Kordylewski, had confirmed its existence. In addition to the Moon, our planet has other celestial bodies orbiting relatively stable around it.
Multiple scientists consider it risky to classify the Kordylewski clouds as satellites, but beyond the thousands of artificial satellites and devices that humans have sent into space, it is striking to know that the Earth maintains natural elements around it, beyond the Moon itself.
Two large dust clouds concentrated at the Lagrange points
Kordylewski clouds are two large concentrations of dust located at Lagrange points L4 and L5 of the Earth-Moon system. These are two of the five points where the gravitational attraction of both the Earth and the Moon exert a combined force that allows a stable location.
In the case of these Kordylewski clouds, observations suggest that they move around these points in ellipses, having remained at that location, some 400,000 kilometers from Earth, for at least several decades.
Following the publication in ‘Monthly Notices of the Royal Astronomical Society’ by two Hungarian astronomers, Kordylewski clouds are considered confirmed. Although, it is still the subject of debate as they are a really tenuous phenomenon and difficult to observe.
“Beyond Kordylewski, a few astronomers also saw the dust cloud at point L5 with the naked eye. Furthermore, in 1966 NASA staged a successful visual observation campaign from an airplane four times: observers described with the naked eye and from the plane very faint nebulosities near points L4 and L5, but currently no one has seen them with the naked eye, perhaps because of the light and air pollution, “Horváth and Slíz-Balogh, the two astrophysicists from the University of Budapest, explain to National Geographic.
As described by the mathematician and popularizer Francisco R. Villatoro, what we had was polarimetric detection and, in his opinion, the images obtained were unclear, and could be an artifact in the telescope lens or some atmospheric phenomenon.
The scientists’ detection was carried out with a linear polarization filter system connected to a camera lens and a CCD detector at the private Slíz-Balogh observatory in Hungary (Badacsonytördemic), as described by the Royal Astronomy Society.
In 2021, several Chinese scientists published a recent open study in SPJ ScienceMag where they again point to its existence based on simulations and establish a plan for observation from space.
More is needed to observe them and check their stability
In response to Xataka, Héctor Vives, astrophysicist at the National Institute of Aerospace Technology (INTA), explains that “according to calculations, the dust particles could be there between a month and several decades. But if these clouds exist, they are extremely thin, and they look very influenced by the solar wind and gravitational interactions“.
These external influences could cause that, despite being at a point of relative stability such as the Lagrange points, perhaps the Kordylewski clouds will end up leaving that location in the coming decades. It is at this point in the research that we find ourselves, to understand if these clouds are really stable enough to be considered to orbit next to our planet or if it is a temporary situation, with a short life on a spatial scale.
“Its existence is not confirmed yet, because probes that have passed through there have not detected anything, and the luminosity from Earth would be little more than the background light, “explains Vives.” The article ends with a detection proposal consisting of sending another probe and an observation campaign with ground-based telescopes. ”
So does the Earth have more than one satellite? “Being only dust particles, I would not call them satellites”, explains the astrophysicist. Neither pseudo-satellite seems to convince him: “pseudo-satellite is used in British English for devices that are placed in the atmosphere at a high altitude. And ‘pseudomoon’ is used for rocks that are almost orbiting the Earth for a while”.
“There is no definition that specifies the minimum size of a satellite. Sometimes large chunks in Saturn’s rings are called “moonlets”, but these dust particles would be even less than that … “, explains Vives.
What is the use of fully confirming the existence of these Kordylewski clouds? Vives explains to us that it would be “a way to access interplanetary dust with a somewhat higher density, which would facilitate its collection and study “.
“It could make it possible to study interstellar dust a little better, if it is mixed with that of the solar system. The published studies also say that there is a kind of potential barrier between the vicinity of the Earth and the regions where those clouds would be, so the dust collected there would be less contaminated by human activities (rocket fuel, etc.) “, says the astrophysicist.
Image | POT