Аннотация:The turbulence of intracluster gas in galaxy clusters and interstellar gas in galaxies can act as a dynamo generating chaotic magnetic fields. These fields are concentrated in ropes. The field strength within the ropes is close to equipartition with turbulent kinetic energy. These results favorably agree with high-resolution observations of the galaxy cluster around Cyg A and correlation analysis of the Galactic nonthermal background. Ropy magnetic fields in interstellar gas lead to observable variations of, e.g., the Faraday depth at time scale of 1 month.