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Earth may have a pair of 鈥済host moons鈥�, translucent clouds of dust that orbit along with our moon. These clouds, which could be up to 100,000 kilometres across, were predicted in 1951, and聽new pictures seem to show they exist.

The Earth-moon system has a set of five gravitational balance points, where the gravitational forces from Earth and the moon balance out. At these spots, called Lagrange points, objects can get caught, never being pulled down to Earth or the moon.

In 1951, astronomer J贸zef Witkowski predicted that interplanetary dust should collect at two particular Lagrange points that are each about 400,000 kilometres from Earth聽and about 400,000 kilometres from the moon, forming equilateral triangles. Then, in 1961, astronomer Kazimierz Kordylewski took the first pictures that seemed to show bright spots near these areas. The collected dust clouds are named Kordylewsi clouds, after him.

But because these clouds are so tenuous and dim, it鈥檚 been difficult to observe them definitively, and astronomers have debated if they really do exist. A Japanese spacecraft that flew through the Lagrange points in the early 1990s did not find a clear increase in dust, adding credence to the idea that theses ghost moons may only be theoretical.

But now new pictures appear to capture one of the聽Kordylewski clouds in impressive detail. G谩bor Horv谩th at E枚tv枚s Lor谩nd University in Hungary and his colleagues took pictures of one of these ghostly satellites using filters designed specifically to pick up light that鈥檚 been bounced around by dust grains.

They found lots of this polarised light in the area where we鈥檇 expect one of the Kordylewski clouds to be. Their observations match patterns seen vaguely in earlier, lower-quality images. 鈥淲e are sure that these clouds are there,鈥� says Horv谩th.

Nevertheless, some other astronomers are not convinced that these observations actually show any difference from the surrounding areas. 鈥淩ather than a 鈥榮moking gun鈥�, this latest paper seems to be more like the smell of gunsmoke,鈥� says Anthony Dobrovolskis at聽the SETI Institute in California.