The sun flings out solar wind particles in much the same manner as a garden sprinkler throws out water droplets.
The artist's drawing of the solar wind flow was provided courtesy of NASA.

The Spiral of the IMF

The solar wind is formed as the Sun's topmost layer blows off into space carrying with it magnetic fields still attached to the Sun. Gusts and disturbances form in the solar wind associated with violent events on the Sun.

Because the Sun spins but particles leave the surface headed directly into space, particles appear to flow into space as if they are spiraling out from the Sun, as shown in this figure. The figure shows what is referred to as the "spiral angle" of the IMF (interplanetary magnetic field).

For a planet to be affected by a blob of material being ejected by the Sun, the planet must be in the path of the blob, as dictated by where the planet is relative to the spiral path of the material.

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