From January 15-16 a stream of cosmic dust - the remains of the tail of the recently disintegrated comet ISON - will hit the Earth. If the particles are large enough, Earth dwellers will see a "meteor shower." However, another phenomenon is more likely - noctilucent clouds. Scientists will try to collect particles of dust, which will fall to the Earth: possibly containing the oldest Solar System material, perhaps, even with blocks of organic matter.

At the end of November, ISON came to its one and only fatal date with our Sun. It was born in the Oort cloud - a giant sphere consisting of ice blocks surrounding the Solar System. Long ago when there were not even bacteria on the young Earth, ISON began its slow fall to the Sun, gradually accelerating. Its substance bears an untouched imprint of the interstellar medium. And there will be a chase after it on the Earth, head of the CryoAstrobiology laboratory of the St. Petersburg Nuclear Physics Institute Sergey Bulat explains.

"When the comet was heading to the Sun, it already possessed a train of gas and dust. Now, in mid-January, the Earth is included in this train, which existed before its approach to the Sun. Our task is to gather the remains of this dust, which were not exposed to heating. It is 4 billion years old. The emphasis is made on small dust particles, whose size is no more than a few microns. The reason: while entering the Earth's atmosphere even at high speeds, these particles do not warm up to such a degree that makes all organic matter, which might be included in them, evaporate," he said.

The collection of dust particles will be carried out three times until the end of January by members of the Russian expedition in the Antarctic, the cleanest place on Earth. The frozen material will be delivered from the Vostok station to the laboratory and examined under an electron microscope, Sergey Bulat says.

"The main thing is a focus on carbon compounds. Maybe there are blocks of life, nucleotides or amino acids. If we arrange these particles correctly, then we can answer the question: Were there some blocks of life at the moment of the Earth's formation or not?" Bulat said.

Melted down by the heat of the Sun, the comet was completely ruined. Its remains would have also been of interest to the science. Unfortunately, they will not intersect with the Earth, head of the Department of Physics and Evolution of Stars of the Institute of Astronomy of the RAS Dmitry Wiebe says.

"In December, the Hubble telescope was looking for a cloud of fragments left by the comet after its flight near the Sun. It is very far from the Earth, and a collision with it is not dangerous for us: we will not be in this area of space. All we can see are particles that the comet lost just before its rendezvous with the Sun," he said.

However, the scientist doubts that the particles of dust from the comet's tail will fall in Antarctica before the end of January.

"Fine dust will slow down in the atmosphere and will very slowly fall down together with the rest of the cosmic dust, which the Earth gathers during its motion. Will it be possible to confidently link these particles to comet ISON? Even if we find these particles and determine their chemical composition, it will be difficult to link them to a particular celestial body," Dmitry Wiebe said.

According to the earthsky.org Internet portal, the smallest particles of the comet can wander in the air flows for up to several months, causing a beautiful phenomenon - noctilucent clouds. And most likely, there will be no "meteor shower."

However, comets are poorly explored and unpredictable objects, thus, any surprises are possible. And ISON has already sprung one of them: the forecast, according to which it was to become one of the brightest comets of the century and even to overshadow the full Moon, did not come true. This would have happened if the celestial body had not disintegrated prematurely.

Source: Voice of Russia