By Elton Gomes
After more than half a century of speculation, Hungarian astronomers and physicists say that they have finally confirmed the existence of two Earth-orbiting moons entirely made of dust. This means that, in addition, to the already existing moon, our Earth has two additional moons made completely out of dust.
A team of Hungarian astronomers and physicists has confirmed that these moons, or dust clouds, move in tandem with the Earth and Moon at a stable 4,00,000 kilometres from the Earth. The clouds are known to move in a triangular motion.
The study has been published in the Monthly Notices of the Royal Astronomical Society. It picks up from a 1961 study conducted by Polish astronomer Kazimierz Kordylewski, who reported that he saw patches at the L4 and L5 Lagrange points. Kordylewski proposed that these patches were dust clouds. The recent study only confirms Kordylewskis speculations.
According to the current study, the new moons are completely made up of extremely tiny dust particles measuring less than one millimetre in size and reflect light rather faintly. This was the reason why they were difficult to observe and study in the first place, though they were located at around the same distance as the Moon from the Earth.
Kordylewski clouds
In 1961, Kordylewski had observed these moons for the first time, and they were later named after him as Kordylewski Dust Clouds (KDCs). However, several questions have been raised over their existence, and not many accurate models or simulations of these objects are available.
In the current study, Gábor Horváth, a physicist at Eötvös Loránd University, and his team used special filters on their cameras. The filters helped in polarising incoming light to catch hold of and study the scattered light from the dust particles inside these moons. With the collected data, the team established that the KDCs are spread across an expanse of 1,00,000 km by 70,000 km in space.
The Kordylewski clouds are two of the toughest objects to find, and though they are as close to Earth as the moon, are largely overlooked by researchers in astronomy, said the studys coauthor Judit Slíz-Balogh, an astronomer at Eötvös Loránd University, National Geographic reported. It is intriguing to confirm that our planet has dusty pseudo-satellites in orbit alongside our lunar neighbor.
Lagrange points
Speculations about Earth having multiple moons have been deliberated over by scientists since a long time. It was realised that even if additional moons did exist, they could only do so in stable points within the Earths orbit.
Lagrange points are such stable points in an orbit where the pull of gravity working from two opposing celestial bodies is balanced due to the centripetal force of their orbits. Thus, an object at a Lagrange point will always remain fixed at a constant distance from both the moon and the Earth.
Kordylewski was able to identify two Lagrange points L4 and L5 where he came across the first of the two dust clouds orbiting Earth.
Will the new moons be of any help?
These huge clouds of dust could help in space exploration efforts with regards to fuel consumption and safety issues. Sometimes, satellites need to be parked at Lagrange points so that the spacecraft consumes minimal fuel and can still stay in orbit.
In addition, Lagrange points could be used as transfer stations for Mars missions. Only time will tell whether astronomers come across more such dust moons in proximity with Lagrange points.
Elton Gomes is a staff writer at Qrius