Astronomers figured out how fast the dark matter flying through Earth

© RIA Novosti / Vitaly to Timepiece potamanthidae in the sky that is observed in the Krasnodar region during the meteor shower the PerseidsAstronomers figured out how fast the dark matter flying through Earth© RIA Novosti / Vitaly to Timepiece the image Bank

. Observations of the oldest stars in the Galaxy have helped astrophysicists to figure out what the speed of dark matter in the vicinity of the Earth and the Sun is unexpectedly low, making it difficult to find her in the future, according to a paper published in the journal Physical Review Letters.

«When a particle of dark energy collides with the nucleus of the atom «normal» matter, the process of their collision like what happens when two billiard balls strike each other. The consequences of this «accident» depend on two parameters – the masses of particles and their velocity. In other words, the faster moving dark matter, the more noticeable are traces,» says Mariangela Lisanti (Mariangela Mary Jarvis from United Kingdom) from Princeton University (USA).

Quite a long time, scientists believed that the universe consists of visible matter, the basis of stars, black holes, nebulae, clusters, dust and planets. But the first observations of the speed of the stars closest to us galaxies showed that the lights on their edges moving with impossibly high speed — about 10 times higher than shown by the calculations on the basis of the masses of all stars.

The reason for this, as scientists believe, was the so-called dark matter — the mysterious substance, which accounts for about 75% of the mass of all matter in the Universe. Usually, each galaxy is about 8-10 times more dark matter than visible, and this dark matter holds the stars in place and not allow them to «scatter».

In recent years, thanks to the pictures some of the relatively little-studied galaxies received «Hubble», scientists began to notice that many small and dwarf galaxies behave quite differently, as the theories predict their device, taking into account the existence of this mysterious substance.

Additional issues as noted Lisanti, creates what today’s astronomers and cosmologists don’t know how fast moving dark matter in our Galaxy and its closest neighbors, which significantly complicates the work «direct» detectors for dark matter, trying to catch traces of her collisions with atoms of xenon-137 and other rare noble gases.

Her team found a way to solve this problem, drawing attention to one interesting fact from the history of the life of the most ancient stars in the milky Way. These lights, according to the astronomers, were born 10-12 billion years ago, at a time when our Galaxy is only beginning to form and actively absorbed a neighbouring dwarf galaxy.

At the time, according to the researchers, the so-called halo — «donut» of dark matter surrounding the milky Way and other star cities — has not yet formed, as the Galaxy constantly received new stocks of this mysterious substance, followed by a cloud of gas and newborn stars.

For this reason, the elderly luminaries that live today on its outskirts, should on average move with the same speed at which dark matter rotates around the center of the milky Way that can be used to calculate this parameter, not having a clue about other properties of this mysterious substance.

Following this idea, the researchers tried to calculate the speed of the dark matter in the vicinity of the Earth using a map of the night sky, prepared by the SDSS project, a computer model of the Galaxy.

These measurements unexpectedly showed that dark matter located near the Solar system should be moving noticeably slower than that predicted by the theory. This discrepancy, as noted Lisanti and her colleagues, talking about serious gaps in the theory, which can seriously interfere with physicists in the search for traces of this elusive substance.

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