Not too long ago, people believed that the sun and all the planets rotated around the Earth.

The Greeks had the opposite model, that the stars and the sun rotated around the earth.

Nor did it escape his attention that the sun itself rotated on its axis in the same sense.

This sun, as the core, rotates in the opposite direction to the moving crust.

The sun and planets rotate in the same direction.

But he then realised that the Sun is rotating.

This suggested that the Sun rotated on its axis, which had been postulated before but never backed up with evidence.

Since the sun rotated every twenty-seven days, these disturbances often recurred a month later.

As the Sun rotates once in about 27 days, the magnetic field transported by the solar wind gets wrapped into a spiral.

By contrast, the Sun only rotates once every 25 - 35 days, with an equatorial velocity of 1.994 km/s.