As it was announced in the journal Science that 36 out of millions of dust particles surrounding Saturn’s orbit appear to be from outside the Solar System. The Cassini probe has been floating along Saturn’s orbit for over a decade.

The theory is that the dust grains come from another planetary or stellar system as they travel at different speeds and paths when compared to other particles that float along Saturn’s orbit. They also spot a different mix of elements when compared to local dust particles.

Of the millions of dust grains Cassini has sampled from Saturn’s orbit, at least 36 of them appear to have come from beyond our solar system. Credit: NASA

The research

The analysis of the particles was performed by Cassini scientists, mainly of European institutions. The probe had the task of studying the planet, its many moons, and rings. Most of the dust grains that were analyzed throughout the years were originated on Saturn’s moon Enceladus, which happens to have a geologically active surface.

Mario Trieloff, an earth scientist at Heidelberg University where the dust detector on the probe was designed, commented that “interstellar dust is one of the last bastions of unknown in space, its individual particles being only about 200 nanometers in size and very hard to find.”

The composition of the 36 particles shows to be very similar one to another, displaying a mix of important rock-forming elements including iron, calcium, and magnesium. Researchers argue that, although the dust particles are minuscule, it is possible to find a collection of the elements that make up the cosmos in this type of samples. The research has shown that some of the analyzed particles do not originate from our native Solar System.

The theory is that the 36 dust particle, traveling at over 72,000 kilometers per hour, had to be formed in an interstellar medium thanks to the action of supernova explosions, making it through hundreds of years before arriving at Saturn’s orbit.

Interstellar dust has already been found, as in the 1990’s, NASA’s Ulysses mission managed to pick up important data about this phenomenon. The dust found on such occasion was determined to have formed on a nearby interstellar cloud that our Solar System is traveling through.

“From that discovery, we always hoped we would be able to detect these interstellar interlopers at Saturn with Cassini,” Nicolas Altobelli, one of the scientists of the Cassini project, said.

The particles detected by Cassini largely differ from other samples of cosmic dust; they appear to be strangely uniform thanks to the prolonged interaction with the interstellar medium.

Altobelli commented that the Cassini-Huygens mission would allow space scientists to gain much more information by obtaining samples of dust that are impossible to obtain in a different way.

Source: Science Daily