Scientists from Spain and Great Britain have come to the conclusion that a "wind" of dark matter passes through the solar system at a speed of 500 kilometers per second. This stream is gravitationally related to the stellar stream S1, which remained after the absorption of the dwarf galaxy by the Milky Way. The researchers' article was published in the journal Physical Review D.
S1 is a group of 34 stars that pass through the vicinity of the solar system in the opposite direction to the rotation of the Milky Way. It was discovered last year by analyzing data from the Sloan Digital Sky Survey (SDSS), a celestial mapping survey, and the Gaia Space Telescope.
The total mass of S1 is comparable to the mass of a dwarf galaxy in the constellation Fornax, so scientists believe that the stellar stream should be associated with a dark matter halo.
According to the ΛCDM (Lambda-Cold Dark Matter) model, in addition to the usual baryonic matter that makes up stars and galaxies, there is dark matter, which makes up 22 percent of all matter in the Universe. The conclusion about its existence was made on the basis of observation of astronomical objects, which behaved as if they were influenced by mass hidden from direct observation.
It is assumed that dark matter interacts with ordinary matter only through gravitational forces, so it cannot be detected through the registration of electromagnetic radiation.
The researchers used a mathematical model to determine how S1 affects the distribution of dark matter in the vicinity of the solar system. Based on this, they calculated how the stellar flow affects the probability of detecting WIMPs (WIMPs) - hypothetical particles that make up dark matter. If vimps exist, then they can be detected by detecting the light emitted by detectors when they are scattered by atomic nuclei.
However, scientists have come to the conclusion that WIMP detectors are unlikely to be able to record these events. More sensitive are axion detectors - hypothetical particles that are another candidate for the role of dark matter.