Testing for an attractor in the low-speed solar wind flow

We analyse a time series of velocities of the low-speed stream measured by the Hellos spacecraft in the inner heliosphere. We use moving average and singular-value decomposition filters to give a faithful representation of the solar wind nonlinear behavior. We have shown that trajectories describing the system in the inertial manifold of phase space asymptotically approach the attractor of low-dimension. The obtained characteristics of the attractor are significantly different from those of the surrogate data. Thus these results show that the inner heliosphere is nonlinear and likely a deterministic chaotic system.