Another possible effect is the variation in the intensity o…

Another possible effect is the variation in the intensity of galactic cosmic rays (high-energy particles originating outside the solar system) that the sun and the solar system are exposed to. The galactic magnetic field and the distribution of cosmic ray sources are not uniform across the galaxy, so the cosmic ray intensity may vary as the solar system moves through different regions. However, the effects of these variations on the sun are not well understood and are likely to be very small.